Do I need a UPS?

Is it essential to have a Mac compatible one?
Andy Hewitt wrote on :

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

We do suffer with a lot of 'brown outs' here, and the occasional flash power cut (like the recent one).

I'm presuming a UPS will alleviate this issue, but I've never needed to look into these before, so have a couple of queries.

I'm assuming that I'll need to more or less match the maximum power consumption of my Mac - the dual G5 1.8 rates at 605W. Looking around this would suggest I need at least a 1000VA UPS, possibly may be better at 1200VA (going by the published ratings).

Is it essential to have a Mac compatible one? Again, I'm assuming that this will only matter if I want it to shut down the Mac properly in the event of a sustained power outage.

A little browse around various sites had found a couple of reasonably priced possibilities - one from Unitek (Misco are doing a 1600VA one for just under £90), and there seems to be a 100VA Trust jobby around too. There's also a company on eBay doing refurbed (i.e fitted with new batteries and 12month wrty) APC 1200VA units.

Any advice?

Woody replied on :

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

We do suffer with a lot of 'brown outs' here, and the occasional flash power cut (like the recent one).

That is why I got mine, after moving to the country. The power was inversely proportional to the rain.

I'm presuming a UPS will alleviate this issue, but I've never needed to look into these before, so have a couple of queries.

Is it essential to have a Mac compatible one? Again, I'm assuming that this will only matter if I want it to shut down the Mac properly in the event of a sustained power outage.

Never bothered connecting mine as the power was only ever out short periods of time, and mine was on a linux server anyway. I think pretty well everything should be able to talk to an APC anyway.

A little browse around various sites had found a couple of reasonably priced possibilities - one from Unitek (Misco are doing a 1600VA one for just under £90), and there seems to be a 100VA Trust jobby around too. There's also a company on eBay doing refurbed (i.e fitted with new batteries and 12month wrty) APC 1200VA units.

I would go for the one whose name was closer to APC. I bought mine on eBay (against advice to never buy a UPC on eBay) and it has been fine. It is an APC something, with USB.

Andrew Stephenson replied on :

In article 1hwy410.15q7jlg1jefmfvN%wildrover.andy@redacted.invalid wildrover.andy@redacted.invalid "Andy Hewitt" writes:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

[...]

Any advice?

Look into the cost of replacing the batteries. They will need changing periodically, AIUI, even if the UPS never has to save your computer's bacon.

Andy Hewitt replied on :

Woody usenet@redacted.invalid wrote:

Is it essential to have a Mac compatible one? Again, I'm assuming that this will only matter if I want it to shut down the Mac properly in the event of a sustained power outage.

Never bothered connecting mine as the power was only ever out short periods of time, and mine was on a linux server anyway. I think pretty well everything should be able to talk to an APC anyway.

Righto.

A little browse around various sites had found a couple of reasonably priced possibilities - one from Unitek (Misco are doing a 1600VA one for just under £90), and there seems to be a 100VA Trust jobby around too. There's also a company on eBay doing refurbed (i.e fitted with new batteries and 12month wrty) APC 1200VA units.

I would go for the one whose name was closer to APC. I bought mine on eBay (against advice to never buy a UPC on eBay) and it has been fine. It is an APC something, with USB.

Yes, they do seem to be about the most popular brand. Those refurbs look OK on the face of it, so I might consider one.

Andy Hewitt replied on :

Andrew Stephenson ames@redacted.invalid wrote:

In article 1hwy410.15q7jlg1jefmfvN%wildrover.andy@redacted.invalid wildrover.andy@redacted.invalid "Andy Hewitt" writes:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

[...]

Any advice?

Look into the cost of replacing the batteries. They will need changing periodically, AIUI, even if the UPS never has to save your computer's bacon.

Yes, I gather they're about £60 a set usually. Probably not bad considering how much large capacity batteries cost in other applications (some proprietry camera batteries for example).

Andy Hewitt replied on :

Woody usenet@redacted.invalid wrote:

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

We do suffer with a lot of 'brown outs' here, and the occasional flash power cut (like the recent one).

That is why I got mine, after moving to the country. The power was inversely proportional to the rain.

I've no idea what's happening here, but it occurs frequently, we get a really bad 'brown-out' almost ever evening.

I'm presuming a UPS will alleviate this issue, but I've never needed to look into these before, so have a couple of queries.

Is it essential to have a Mac compatible one? Again, I'm assuming that this will only matter if I want it to shut down the Mac properly in the event of a sustained power outage.

Never bothered connecting mine as the power was only ever out short periods of time, and mine was on a linux server anyway. I think pretty well everything should be able to talk to an APC anyway.

Ok.

A little browse around various sites had found a couple of reasonably priced possibilities - one from Unitek (Misco are doing a 1600VA one for just under £90), and there seems to be a 100VA Trust jobby around too. There's also a company on eBay doing refurbed (i.e fitted with new batteries and 12month wrty) APC 1200VA units.

I would go for the one whose name was closer to APC. I bought mine on eBay (against advice to never buy a UPC on eBay) and it has been fine. It is an APC something, with USB.

Understood. However, looking at my budget level, I had the option of a new Unitek, Trust, Belkin or a S/H APC.

The APC model I was considering didn't have USB anyway, and the Unitek didn't seem that it might be compatible with OSX, and I couldn't find any user reviews (or any reviews come to that).

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

Cheers.

Woody replied on :

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Woody usenet@redacted.invalid wrote:

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

We do suffer with a lot of 'brown outs' here, and the occasional flash power cut (like the recent one).

That is why I got mine, after moving to the country. The power was inversely proportional to the rain.

I've no idea what's happening here, but it occurs frequently, we get a really bad 'brown-out' almost ever evening.

Went through a phase of that. I reckon it was the cows perching on the power lines.

I'm presuming a UPS will alleviate this issue, but I've never needed to look into these before, so have a couple of queries.

Is it essential to have a Mac compatible one? Again, I'm assuming that this will only matter if I want it to shut down the Mac properly in the event of a sustained power outage.

Never bothered connecting mine as the power was only ever out short periods of time, and mine was on a linux server anyway. I think pretty well everything should be able to talk to an APC anyway.

Ok.

A little browse around various sites had found a couple of reasonably priced possibilities - one from Unitek (Misco are doing a 1600VA one for just under £90), and there seems to be a 100VA Trust jobby around too. There's also a company on eBay doing refurbed (i.e fitted with new batteries and 12month wrty) APC 1200VA units.

I would go for the one whose name was closer to APC. I bought mine on eBay (against advice to never buy a UPC on eBay) and it has been fine. It is an APC something, with USB.

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

That is way more than I paid for my USB APC 1000VA (£70), although that was almost 2 years ago now. I don't know what you are powering but I have powered a dual xeon linux twin disk server, a wireless network connector, an adsl router and on occasion an athlon 64 workstation off it. It never went over 3 bars of 5. in fact for a while it powered a fully loaded Dell quad xeon with 5 raid disks, until i couldn't put up with the noise any more!

Andy Hewitt replied on :

Woody usenet@redacted.invalid wrote:

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

That is way more than I paid for my USB APC 1000VA (£70), although that was almost 2 years ago now.

Blimey. I missed the boat there then. A brand new 1000VA APC, with USB, is on eBay at about £130 (with postage), retailers are nearer to £200. The refurbed 1400VA ones are at £120 (with postage) - again retail new, well over £200.

The Trust 1200VA and the Unitek 1600VA ones were about £90.

I don't know what you are powering but I have powered a dual xeon linux twin disk server, a wireless network connector, an adsl router and on occasion an athlon 64 workstation off it. It never went over 3 bars of 5. in fact for a while it powered a fully loaded Dell quad xeon with 5 raid disks, until i couldn't put up with the noise any more!

It'll be powering my G5 dual 1.8, with 4.5GB of RAM, an upgrade graphics card (ATI 9800XT). Two 320GB internal drives. Plugged into the ADC port is a Formac 17" TFT monitor (so is also powered off the G5). I also run a 20" widescreen TFT monitor too (which is set as my main screen, so will have to be powered).

Apple's data sheets say the dual G5 can go up to 605 Watts.

I'd also like to run my external 5-1/4" twin drive FW800 box (with 300GB and 160GB SATA drives in it). Not forgetting the ADSL wireless router too (this could be needed if I was doing a backup from the iBook over the network).

If it'll take it, I could also run Emily's 2.8GHz Celeron Fujitsu box as well, although that's running a hefty 17" LG CRT monitor too.

Woody replied on :

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Woody usenet@redacted.invalid wrote:

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

That is way more than I paid for my USB APC 1000VA (£70), although that was almost 2 years ago now.

Blimey. I missed the boat there then. A brand new 1000VA APC, with USB, is on eBay at about £130 (with postage), retailers are nearer to £200. The refurbed 1400VA ones are at £120 (with postage) - again retail new, well over £200.

Just had a look. The guy I bought mine off is now just selling laptops by the look of it.

The Trust 1200VA and the Unitek 1600VA ones were about £90.

Bit of a difference. I can see why though, I guess in some way you pay for the name, as if I was buying one for my business I would just go straight for the APCs, and probably wouldn't look at others (they have good upgrade policies too, and you know the batteries are going to be available for a long time).

I don't know what you are powering but I have powered a dual xeon linux twin disk server, a wireless network connector, an adsl router and on occasion an athlon 64 workstation off it. It never went over 3 bars of 5. in fact for a while it powered a fully loaded Dell quad xeon with 5 raid disks, until i couldn't put up with the noise any more!

It'll be powering my G5 dual 1.8, with 4.5GB of RAM, an upgrade graphics card (ATI 9800XT). Two 320GB internal drives. Plugged into the ADC port is a Formac 17" TFT monitor (so is also powered off the G5). I also run a 20" widescreen TFT monitor too (which is set as my main screen, so will have to be powered).

Apple's data sheets say the dual G5 can go up to 605 Watts.

I'd also like to run my external 5-1/4" twin drive FW800 box (with 300GB and 160GB SATA drives in it). Not forgetting the ADSL wireless router too (this could be needed if I was doing a backup from the iBook over the network).

If it'll take it, I could also run Emily's 2.8GHz Celeron Fujitsu box as well, although that's running a hefty 17" LG CRT monitor too.

I never ran any monitors off my UPS though, so maybe that was the difference. I just had it to protect the servers in case the power went out, and the PC I was working on (as it was my work PC). Anything else I didn't mind going off.

Odie Ferrous replied on :

Andy Hewitt wrote:

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

Andy,

If there's any chance you could cancel the Belkin, I'd do so.

I once had a Belkin 1200VA UPS.

We experienced a (very rare) power cut while we were out.

On arriving home, the children were sitting around, and said the power had been down for 10 minutes.

I walked into my office, to find smoke and the smell of burning streaming (coursing; billowing even) out of a monitor.

It destroyed a DC adaptor also connected, and damaged some of the components on a then-very-expensive dual core processor computer.

Of course, Belkin immediately replaced it with a 1500VA the very next day, and took away the 1200VA.

And, of course, their "engineers" found nothing to be at fault.

And to top it all, they were sitting on the evidence.

I then did some googling, only to find out that Belkin are vastly inferior to APC, and that I wasn't alone in my experience.

I purchased APC to replace the Belkin, and won't touch Belkin UPS products again.

Odie

Andy Hewitt replied on :

Woody usenet@redacted.invalid wrote:

The Trust 1200VA and the Unitek 1600VA ones were about £90.

Bit of a difference. I can see why though, I guess in some way you pay for the name, as if I was buying one for my business I would just go straight for the APCs, and probably wouldn't look at others (they have good upgrade policies too, and you know the batteries are going to be available for a long time).

If I could have got a 1200VA APC with USB at a price nearer to the others, I would have just gone for it, but at double the price!

If it'll take it, I could also run Emily's 2.8GHz Celeron Fujitsu box as well, although that's running a hefty 17" LG CRT monitor too.

I never ran any monitors off my UPS though, so maybe that was the difference. I just had it to protect the servers in case the power went out, and the PC I was working on (as it was my work PC). Anything else I didn't mind going off.

It'll need to at least power the G5 and both monitors, and preferably the external drive box, just so I have a chance to finish saving stuff.

Andy Hewitt replied on :

Odie Ferrous odie_ferrous@redacted.invalid wrote:

Andy Hewitt wrote:

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

Andy,

If there's any chance you could cancel the Belkin, I'd do so.

I once had a Belkin 1200VA UPS.

We experienced a (very rare) power cut while we were out.

On arriving home, the children were sitting around, and said the power had been down for 10 minutes.

I walked into my office, to find smoke and the smell of burning streaming (coursing; billowing even) out of a monitor.

It destroyed a DC adaptor also connected, and damaged some of the components on a then-very-expensive dual core processor computer.

Of course, Belkin immediately replaced it with a 1500VA the very next day, and took away the 1200VA.

And, of course, their "engineers" found nothing to be at fault.

And to top it all, they were sitting on the evidence.

I then did some googling, only to find out that Belkin are vastly inferior to APC, and that I wasn't alone in my experience.

I purchased APC to replace the Belkin, and won't touch Belkin UPS products again.

Hmm, I did a lot of Googling too, and found nowt like that at all? In fact all my findings were exactly the opposite.

........ So I've been off browsing some more, and looked up info for both APC and Belkin UPS devices. It's a draw for me. I found one instance of a Belkin almost catching fire, but it looks like the chap had used a surge protector inline with the UPS, and possibly also had poorly fitted plugs (US versions).

I also came across a similar fate for an APC unit, which had its batteries leak while in normal use. I've also seen a couple of mentions of batteries not sustaining their charge when they were needed.

None of these were current models though, and I can only find mostly 4 and 5 star (out of 5) ratings for both brands.

I realise there's the old 'once bitten' saying, but it's possible they will have sorted any known issues. Historically, many manufacturers have screwed up at one time or another, even the best of them.

Odie Ferrous replied on :

Andy Hewitt wrote:

Odie Ferrous odie_ferrous@redacted.invalid wrote:

Andy Hewitt wrote:

I've actually settled on a Belkin 1200VA Universal one. Simply because it is cheaper than a second hand APC, and it has OSX software available, if OSX doesn't recognise it anyway. Not only that, it has normal 3 pin sockets on it, rather than the IEC connectors, so no messing about with new cables either. It also got good user reviews too, in fact a full set of stars wherever I looked. If you're interested £106 at eBuyer.

Andy,

If there's any chance you could cancel the Belkin, I'd do so.

I once had a Belkin 1200VA UPS.

We experienced a (very rare) power cut while we were out.

On arriving home, the children were sitting around, and said the power had been down for 10 minutes.

I walked into my office, to find smoke and the smell of burning streaming (coursing; billowing even) out of a monitor.

It destroyed a DC adaptor also connected, and damaged some of the components on a then-very-expensive dual core processor computer.

Of course, Belkin immediately replaced it with a 1500VA the very next day, and took away the 1200VA.

And, of course, their "engineers" found nothing to be at fault.

And to top it all, they were sitting on the evidence.

I then did some googling, only to find out that Belkin are vastly inferior to APC, and that I wasn't alone in my experience.

I purchased APC to replace the Belkin, and won't touch Belkin UPS products again.

Hmm, I did a lot of Googling too, and found nowt like that at all? In fact all my findings were exactly the opposite.

........ So I've been off browsing some more, and looked up info for both APC and Belkin UPS devices. It's a draw for me. I found one instance of a Belkin almost catching fire, but it looks like the chap had used a surge protector inline with the UPS, and possibly also had poorly fitted plugs (US versions).

I also came across a similar fate for an APC unit, which had its batteries leak while in normal use. I've also seen a couple of mentions of batteries not sustaining their charge when they were needed.

None of these were current models though, and I can only find mostly 4 and 5 star (out of 5) ratings for both brands.

I realise there's the old 'once bitten' saying, but it's possible they will have sorted any known issues. Historically, many manufacturers have screwed up at one time or another, even the best of them.

This was a couple of years ago, so things may have changed since then. All I know is that professional (i.e. real blue-chip) companies use APC and not Belkin!

Whatever the model you choose, it might be an idea not to connect any displays to the UPS and trust the in-built software to do the job of shutting down the computer. Especially if the display uses quite a chunk of current.

Odie

Andy Hewitt replied on :

Odie Ferrous odie_ferrous@redacted.invalid wrote:

I realise there's the old 'once bitten' saying, but it's possible they will have sorted any known issues. Historically, many manufacturers have screwed up at one time or another, even the best of them.

This was a couple of years ago, so things may have changed since then. All I know is that professional (i.e. real blue-chip) companies use APC and not Belkin!

Understood. However, I just couldn't pass that up at the price difference.

Whatever the model you choose, it might be an idea not to connect any displays to the UPS and trust the in-built software to do the job of shutting down the computer. Especially if the display uses quite a chunk of current.

Well, I can always test it while I'm there at first. Mind you, one of my displays is driven from the ADC port, so it will get powered anyway.

Thanks for the thoughts anyway.

Mark Ingle replied on :

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Understood. However, looking at my budget level, I had the option of a new Unitek, Trust, Belkin or a S/H APC.

At work, we have different models of UPS including APC, Belkin and Unitek. Personally, I prefer the APCs; they have mostly been troublefree and on the SmartUPS models, the display shows more useful information, such as load and battery level. In fact, at home I have one of the old APC UPS's that had 'broken'. Just replaced the batteries with decent Yuasa ones from Maplin, and it's been working fine ever since.

The Unitek's are cheap and cheerful. While some of them have a fancy display, it doesn't really display that much useful information. Oh, and one of them came without batteries, which may indicate quality control isn't so good!

The Belkin models have been fine, though one needs to rely on the software to monitor them as the LEDs on the unit are tiny; we had one unit shutting the computer off because of an overload, though the display seemed to show everything was fine. On the universal model, one of the four power points is surge protection only, which is fine except you would have thought they could have marked it out better

Andy Hewitt replied on :

Mark Ingle markinglenospam@redacted.invalid wrote:

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Understood. However, looking at my budget level, I had the option of a new Unitek, Trust, Belkin or a S/H APC.

At work, we have different models of UPS including APC, Belkin and Unitek. Personally, I prefer the APCs; they have mostly been troublefree and on the SmartUPS models, the display shows more useful information, such as load and battery level. In fact, at home I have one of the old APC UPS's that had 'broken'. Just replaced the batteries with decent Yuasa ones from Maplin, and it's been working fine ever since.

The Unitek's are cheap and cheerful. While some of them have a fancy display, it doesn't really display that much useful information. Oh, and one of them came without batteries, which may indicate quality control isn't so good!

The Belkin models have been fine, though one needs to rely on the software to monitor them as the LEDs on the unit are tiny; we had one unit shutting the computer off because of an overload, though the display seemed to show everything was fine. On the universal model, one of the four power points is surge protection only, which is fine except you would have thought they could have marked it out better

Cheers, that pretty much bears out what I'd found so far.

James Dore replied on :

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Woody usenet@redacted.invalid wrote:

Is it essential to have a Mac compatible one? Again, I'm assuming that this will only matter if I want it to shut down the Mac properly in the event of a sustained power outage.

Never bothered connecting mine as the power was only ever out short periods of time, and mine was on a linux server anyway. I think pretty well everything should be able to talk to an APC anyway.

Righto.

A little browse around various sites had found a couple of reasonably priced possibilities - one from Unitek (Misco are doing a 1600VA one for just under £90), and there seems to be a 100VA Trust jobby around too. There's also a company on eBay doing refurbed (i.e fitted with new batteries and 12month wrty) APC 1200VA units.

I would go for the one whose name was closer to APC. I bought mine on eBay (against advice to never buy a UPC on eBay) and it has been fine. It is an APC something, with USB.

Yes, they do seem to be about the most popular brand. Those refurbs look OK on the face of it, so I might consider one.

I like APC, they're reliable and robust. The batteries are available separately and are hot-swappable (at least on all our Smart-UPS range), and they also make it easy to send them back for recycling.

USB connections 'just work' on macs (got one attached to my PMG5 and it's just there in the Energy Saver control panel).

Cheers,

Andy Hewitt replied on :

James Dore james.dore@redacted.invalid wrote:

Yes, they do seem to be about the most popular brand. Those refurbs look OK on the face of it, so I might consider one.

I like APC, they're reliable and robust. The batteries are available separately and are hot-swappable (at least on all our Smart-UPS range), and they also make it easy to send them back for recycling.

USB connections 'just work' on macs (got one attached to my PMG5 and it's just there in the Energy Saver control panel).

Yes, cheers. Unfortunately the models I was considering weren't USB ones.

J. J. Lodder replied on :

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

We do suffer with a lot of 'brown outs' here, and the occasional flash power cut (like the recent one).

I'm presuming a UPS will alleviate this issue, but I've never needed to look into these before, so have a couple of queries.

I'm assuming that I'll need to more or less match the maximum power consumption of my Mac - the dual G5 1.8 rates at 605W. Looking around this would suggest I need at least a 1000VA UPS, possibly may be better at 1200VA (going by the published ratings).

Depends on what you have in it. With no extras it will use less than max,

Jan

Andy Hewitt replied on :

J. J. Lodder nospam@redacted.invalid wrote:

Andy Hewitt wildrover.andy@redacted.invalid wrote:

Following my recent panic over my failed system after a recent power outage, I'm wondering about getting a UPS.

We do suffer with a lot of 'brown outs' here, and the occasional flash power cut (like the recent one).

I'm presuming a UPS will alleviate this issue, but I've never needed to look into these before, so have a couple of queries.

I'm assuming that I'll need to more or less match the maximum power consumption of my Mac - the dual G5 1.8 rates at 605W. Looking around this would suggest I need at least a 1000VA UPS, possibly may be better at 1200VA (going by the published ratings).

Depends on what you have in it. With no extras it will use less than max,

Well, a Radeon 9800XT card (with a huge fan on it), 4.5GB of RAM, and two 320GB hard drives, oh, and Airport Extreme.