Power supply?

[Despairl]

How big of a power supply do i need to run a 5900xt?

[bobmanfoo]

think 300W+ will do fine

[Beast_USA]

How big of a power supply do i need to run a 5900xt?

What else are you running? more stuff more power :)

1 case fan or 5 case fans?
1 hard drive or 3 or 4 or 5?
CPU? amd or intel

All factor in if you are maxed 5 or 6 fans (120' or 80's), 2 hard drives, DVD+CDR/CDRW, 1 gig plus fast memory, sound card, pci add on card,

more stuff more power maxed out 550w to 600w
Half that much 460 to 500w
Lowest I would ever use 430w (that would be on newer systems)

Pll, Plll, Amd k2, k7, duron 350w

[Despairl]

ok after reading that....i think i'll need a 600 watter...lol....it's a computer i'm building for a friend and P4 3.4E, 3 gigs of ram, etc etc...

[David]

ok after reading that....i think i'll need a 600 watter...lol....it's a computer i'm building for a friend and P4 3.4E, 3 gigs of ram, etc etc...

Yeah, you are looking for a nice big brand name PSU for that monster - Forton/Antec/Sparkle/OCZ 550W would do it nicely.

Welcome to the forums btw :)

[DocGiggs]

bleh, unless you have a ton of hard drives... you won't need much. And that is only if you plan to have them all in continuous operation like as a major file server.

Things to remember when looking at power.

1) The CPU is going to draw the most. Most will draw from 80-110w depending on the type and how far your went in OCing

2) Video cards will draw the second most. That is if it's a newer card. 9800 line, 5800 line, 5900 line, x800 line, and 6800 line will draw almost as much as the CPU under load.

3) continous hard drive, and fast drives like scsi or raptors, will draw off a ton of power. Takes like 4 or 5 drives in continous use to = the power of a CPU though in terms of drawn power.

4) Water cooling setups, *can* draw alot of power. This is mainly because of the pump. A really powerful one that is running of the 12v line will draw a ton of power. A wimpy one will only draw a little. An AC pump you won't have to worry about.


Those are it. Most people can get away with a 350-400w *quality* power supply even with the best CPU, graphics card, and what not. Which is why fortron/sparkle, Antec true, TTGI, PC Power&Cooling, and a couple others are the highly recommended supplies. They provide good power past their rated specs. They also tend to have very good line tolerance and ripple effect. These are important when trying to overclock. For example. Some power supplies will have a 5% or higher tolerance. This means a 12v line with a 5% tolerance can vary between 11.4 and 12.6. Either case can be very bad when overclocking. The ripple is how much it tends to vary all the time. A line that fluctates constantly, like changing every second from 11.4 to 12.6 all the time can kill stuff. Usually a line fluctuates more the bigger the load that is put upon it and as the load starts approaching the max output of the supply. This is why having a *bigger* wattage power supply is nice because you can get less fluctuations.

You really should read the big sticky here posted about *what power supply* as it helps. It will give you a good list of reputable brands of power supplies to choose from. If you want the absolute best supply though the PC Power&cooling is going to be the only supply with the lowest tolerance on all voltage rails, 1% or less, and have the smallest ripple effect under any given load. Then again, you pay a handsome price for a handsome power supply like that as well. This is why people tend to choose the fortron/sparkle (same company) supplies. They have good tolerance at usually 3% and low ripple noise as well. That and they are much cheaper compared to equivically rated power supplies.

[Beast_USA]

ok after reading that....i think i'll need a 600 watter...lol....it's a computer i'm building for a friend and P4 3.4E, 3 gigs of ram, etc etc...


DocGiggs is correct but if you are biulding a E or EE chip system 3 gigs plus.
I'm guessing Raid 0?

The raptors (any raid with 2+ drives) and that e/ee chip with be power hungry. And 6800U major power sucker needs 2 separate 12v rails just for it. (nothing else using those rails per their instructoins for best performance)

You need 550w+ and a good one ....antec or enermax :burn: