Estimating how many Watt PSU u will need?

Apoc1

Junior Member
Jan 14, 2007
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Is there a Website that will let u punch in your system or proposed system and it will let you know how many Watts it will take to run? i know not to skimp on a PSU but 700W to 500W could save me some Dough.
 

rxblitzrx

Senior member
Aug 14, 2006
400
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I was told that anything you build not using SLI can be handled by Seasonic S-12 380W PSU. I have one. Check my sig.
 

dguy6789

Diamond Member
Dec 9, 2002
8,558
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There are some websites that do this, but I would take most of those without much credit. Your best bet would be to tell us what your planned system is and we can give you a much better idea as well as power supply recommendations that are both a good value and known quality.
 

StopSign

Senior member
Dec 15, 2006
986
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Originally posted by: dguy6789
There are some websites that do this, but I would take most of those without much credit. Your best bet would be to tell us what your planned system is and we can give you a much better idea as well as power supply recommendations that are both a good value and known quality.
I think those websites are quite credible. Computers are simply not that power hungry, less the new video cards out there. The only things that take a lot of power are the CPU and video card. An overclocked C2D will draw around 100W max. The video card will vary based on what you're using, but a midrange card like my 7900GS is pretty lightweight since it uses the same amount of power as the 6600GT. Not counting the chipset, next on the list would probably be hard drives. If you add it up, a computer doesn't use that much power. That's why people can afford to leave their machines on at night and not have the hydro bill rip a hole in their pockets.
 
Oct 4, 2004
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PSU requirements are commonly blown out of proportion. Just check the GPU manufacturer's recommendation for the 12V amperage and you will be good.

For instance, this is for an X6800/975XBX2 system with 7900GTX, 8800GTX, X1950XTX and X1950XTX CF respectively. I took the numbers from the Vista runs.

IDLE: 149, 183, 152, 191
LOAD: 191, 279, 290, 401

Keep in mind that Quad-Cores are designed for a 130W TDP while current C2Ds are rated at 65W. A hefty overclock (with a raised vcore) can dramatically increase CPU power draw at peak load. I still believe 500W of power from a quality maker is more than enough for high-end single-GPU rig - even when factoring high OCs.
 

Furen

Golden Member
Oct 21, 2004
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A good PSU that can handle 400W on the 12v rail is probably enough if you don't plan on running multiple video cards and don't plan on doing some crazy overclocking. Hell, even you could probably get away with a PSU with 300W on the 12v rail if you dont plan on overclocking at all.

Keep in mind that when I say "good" I mean decent brands, something that will set you back a good 50 bucks, so buying a $30 sparkle is no good. Personally, I'd recommend Seasonic (they're the best, but priced accordingly) or a Fortron (quite good, in my experience, and cheap). I have used Antecs before and have had no problem with them but I've heard some horror stories recently (and havent bought one in like 3 years). I've also heard that SOME Rosewill PSUs are good but you'd have to look into that yourself.
 

Conky

Lifer
May 9, 2001
10,709
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I run a rock solid overclocked E6400 at 3.2GHz, 4 7200rpm HD's, 2 DVD burners, 8 or 9 fans of various sizes with an older Antec True Power 430. I keep wanting to upgrade it but, hey, it works, and I keep finding other stuff to spend my cash on. :p

I would definitely recommend a more powerful P/S if you are gonna SLI/Crossfire but if not then a quality 500w should do everything just fine. ;) A PC Power & Cooling Silencer 470 ATX at $98 would be awesome. :thumbsup:
 

Brunnis

Senior member
Nov 15, 2004
506
71
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I happen to own an overclocked C2D system and a power meter. The results are pretty interesting. First off, here's the system:

Antec NeoHE 430W
C2D E6600 @ 3GHz (1.15V)
Asus P5B (with the P965 chipset running on 333MHz)
2GB DDR2-833MHz 4-4-4
7900GS @ 520/1440
Soundblaster Audigy 4
Western Digital Caviar SE16 250GB
Lite-On 16x DVD-ROM
2x120mm fans and 1x92mm fan
D-Link DWL-G122 (USB WLAN dongle)
Logitech UltraX Flat USB
Logitech USB receiver

The highest this system has been, power consumption wise, is 170W at the wall socket. That's with both CPU cores and the GPU loaded. Now, this is at the wall socket, which means that the actual power that the PSU delivers is much lower than this. The PSU efficiency is appoximately 80% at this load, which means that the system components need 170*0.8 = 136W.

It's pretty obvious that any decent 300W PSU would be able to handle my system perfectly fine. The funny thing is that if I would ask around on forums, what kind of PSU I should have for a system like this, most would probably recommend 500W+.
 

StopSign

Senior member
Dec 15, 2006
986
0
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Originally posted by: Brunnis
It's pretty obvious that any decent 300W PSU would be able to handle my system perfectly fine. The funny thing is that if I would ask around on forums, what kind of PSU I should have for a system like this, most would probably recommend 500W+.
The OCZ rep here would recommend the GameXtreme 700W.
 

Roguestar

Diamond Member
Aug 29, 2006
6,045
0
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Originally posted by: Brunnis
I happen to own an overclocked C2D system and a power meter. The results are pretty interesting. First off, here's the system:

Antec NeoHE 430W
C2D E6600 @ 3GHz (1.15V)
Asus P5B (with the P965 chipset running on 333MHz)
2GB DDR2-833MHz 4-4-4
7900GS @ 520/1440
Soundblaster Audigy 4
Western Digital Caviar SE16 250GB
Lite-On 16x DVD-ROM
2x120mm fans and 1x92mm fan
D-Link DWL-G122 (USB WLAN dongle)
Logitech UltraX Flat USB
Logitech USB receiver

The highest this system has been, power consumption wise, is 170W at the wall socket. That's with both CPU cores and the GPU loaded. Now, this is at the wall socket, which means that the actual power that the PSU delivers is much lower than this. The PSU efficiency is appoximately 80% at this load, which means that the system components need 170*0.8 = 136W.

It's pretty obvious that any decent 300W PSU would be able to handle my system perfectly fine. The funny thing is that if I would ask around on forums, what kind of PSU I should have for a system like this, most would probably recommend 500W+.

Maybe because the more you're paying for a PSU, generally, the more watts you're getting out of it when in reality what you are aiming for when investing more in a PSU is reliability and more amps on the 12v rail.
 

jose

Platinum Member
Oct 11, 1999
2,079
2
81
One thing to be aware is not all psu's are equal..

one companies 500w is not equal to another's 350w psu..

I like to stick to Antec, OCZ, Zippy, PC P&C, Seasonic, & Enermax psu's..

My current favorite are the Seasonic, OCZ & PC P&C psu's..

Probably cost wise a 500w Seasonic should do you well..

In my lastest soon to be built rig , I'll have a 750w PC P&C w/ a e6600 & 8800 vid card w/ scsi drives...

Regards,
Jose
 

Apoc1

Junior Member
Jan 14, 2007
10
0
0
Wow, thanks for the response all, very informitive. I was planning on buying a Corsair 620W PSU for this rig which i will post at the bottum. But maybe i will go with a 400-500 Watt Seasonic since I hear Seasonic produces the Corsair PSU and then slaps the Corsair label on it. Right now Im planning on buying this stuff in April after compaines have had time too catch up with Vista and to give some time for these prices to fall. If the prices dont come down in 3 Months considerably then i will rethink my choices. When middle of the road DX10 cards and the new AMD chips step in the door this build should be cheaper. With some tweaking of course, and help from the forums.

Proposed Rig