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Strahd
03-21-05, 11:01 AM
Below was taken from an article in PC World and I wanted everyone's input as to how accurate it is:

CPU

AMD Athlon 64/64 FX 90-110
AMD Thunderbird 50-60
AMD Athlon XP 50-80
AMD Duron 40-60
Intel Pentium 4 60-100
Intel Pentium 3 25-40
Intel Celeron 30-60

Graphics Card

Basic 25
High-Performance 35-100+

Other

Motherboard 18-28
Optical drive 25-35
Hard drive 25
Memory module (each) 7-12
Unpowered USB/Firewire device 5-10
PCI sound card 5-10
Additional PCI card 5
Floppy drive 5
Fan 3
Keyboard & mouse 6

If this is pretty accurate, my 500w power supply is pumping out about 430 watts under full load. It is also noted here that you should add 30% to the number to be safe.

Comments?

Strahd

Daneel Olivaw
03-21-05, 11:50 PM
In general, http://www.jscustompcs.com/power_supply/ seems fairly close to the thruth.

TierMann
03-22-05, 12:16 AM
That link is dead. Has been for a while. Google cache has a copy though.

couple more here...
http://www.3dcool.com/PWC.asp
http://www.casemodgod.com/psu_calculator.htm

I don't trust the second one all that much since it's saying half of what a 6800gt uses.

Strahd
03-22-05, 10:20 AM
That link is dead. Has been for a while. Google cache has a copy though.

couple more here...
http://www.3dcool.com/PWC.asp
http://www.casemodgod.com/psu_calculator.htm

I don't trust the second one all that much since it's saying half of what a 6800gt uses.


Which one would you say is more accurate though?

3dcool.com - 483 watts
casemodgod.com - 370 watts

113w difference is pretty significant. Not sure but my guess would be the 483 watts would be peak max wattage and the 370 is probably closer to actual normal usage. Both seem to agree on several items being the same wattage so I'm not sure.

I basically just wanted to make sure my 500w PSU is enough to handle the load of my rig.

BrianG
03-22-05, 10:56 AM
Honestly, knowing what I know about power from Telecom, you want to overbuild here so I appreciate the higher estimate by 3DCool's calculator. However some PSUs, like OCZ, have a better peak ouput rating make their normal Wattage a bit on the conservative side.

Taking a closer look, it appears that if the Wattage estimates per itme are roughly the same between the two calculators, 3DCool's adds the 30% buffer.

So yeah, 500W should handle what you are building...

ViN86
03-22-05, 11:28 AM
heh it says my minimum is 376W and i have a 380W. talk about cuttin it close, heh :cool:

i get good voltages on my hardware though. 12V rail hits 11.7 at lowest, usually runs at 11.8V-11.9V

TierMann
03-22-05, 01:41 PM
I'd go with 3dcool's since it over estimates. I still don't understand where casemodgod gets their video card wattages from.