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It looks like I've got a dead Antec True 330 power supply in an older desktop that has an Intel D845PESV motherboard, a Pentium 2.4GHz processor, 2 dvd/cd writers, 2 hard drives, and other typical devices.

I have an even older computer that is not being used that has a 200W power supply. Can a 200W power supply drive what I've listed above?

Or, put another way, what is the minimum power supply specs for the above system?

(A new 350W power supply will run me $30--so buying a new one is not a problem--but I'm curious about the question nonetheless).

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up vote 5 down vote accepted

Try this tool which helps you calculate the right size

Sometimes it's worth paying a little more for a more efficient one.

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Came here to post this. +1 – th3dude Sep 18 '09 at 14:42
Even with a rough estimate, I'm over a 200W estimate. Looks like the 200W is definitely not going to do it. Thanks for the link. – Scott Marlowe Sep 18 '09 at 14:47
Ah well as you say PSUs aren't that expensive. – Col Sep 19 '09 at 6:33

I reckon you might just be able to get away with 350W.. I wouldn't risk it at 200W, you'd have trouble running the hard drives and stuff all at the same time.

I'd try to go on the safe side, and find a 400W PSU.

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Not saying it wouldn't work, but 200W does sound a bit low. Personally, I would rather have one that is above what you need and leave it at 50% capacity than getting a low one and running it at 90+.

I build many machines and even with loads of hard drives, graphics cards and more, I have never needed above 550W and for most machines, I use 400W

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My parents' PC (once mine) runs a P4 2.4 quite happily with a 250W supply, including two hard disks, two DVD drives and an old Radeon 9600XT. But i'd still go for at least 300W to give a bit of wiggle room.

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I just did a full install of Xubuntu 10.10 with a 2.4ghz P4, 512mg PC3400 DDR, 40gb Sata drive, IDE DVD drive, running a wireless card and stock graphics (Intel 865glc board). I unplugged the case fan and didn't work the system hard after the install, but it ran Firefox etc. just fine. I think a bit of the big number power supply game is over rated, the 120 watt I had came with a P4 plug so I figured I might as well give it a shot (it is TINY, from a little bitty PC, but it was the only PSU I had out of 6 that didn't have dead caps!).

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The 200w could but you don't mention the video card and if you do things like burn from dvd-dvd etc. You also didn't list the model of the PSU which comes into play if you have a very good one that is actually rated to run at 200W for any length of time it helps. You could have a model that can only run at a 200W load for 10mins.

I would get a newer one that has a better power rating and that wastes less electricity if you can get that 350W and it has an 80plus rating or better.

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200w may not suffice for a 'northwood space heater' at full CPU load, even in combination with a very low spec graphics card.

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