Nvidia 8800gts power supply

[jason93]

I have a ocz modstream 450watt with 26amps on the 12-volt rail. I'm looking to buy a 8800gts soon. The card recommends having 26 amp or more. Do you think my current PS should work ok? I have 2 cd-roms, 2 hard drives and 3 case fans. I'm running a 7950gt as of now with no problems. Let me know if you need anymore info on my system.

 

[Dreven]

Hmm... 60 views and no reply. And, I have a very similar question.

I'm about to put togather:
EVGA 680i
E6600
Zalaman 9700
EVGA 8800GTS
2GB Crucial DDR1000
x2 Segate 320G
x2 Plextar DVD R/W
x4 Case Fan

I plan on doing modest Air O'clocking.

Currently I have this PSU
FSP Group (Fortron Source) AX500-A, 2.0 version, 2 SATA, PCI Express, 500W - Retail
OUTPUT: +3.3V@30A, +5V@28A, +12V1@15A, +12V2@15A, -12V@0.5A, +5Vsb@2.0A
http://www.newegg.com/Product/Product.asp?Item=N82E16817104934&name=Item-#:-N82E16817104934


The thing is I'm going to go SLI when the 8800GTS drop in price a bit. Probably during mid 2007. Until then, if at all possible I'd like to keep the current PSU I have and upgrade it when I actually go SLI.


Will the FSP 500W work for the hardware above and some overclocking? I have no idea.


The retail box of the 8800GTS has this on it:

Minimum of a 400 Watt power supply.
(Minimum recommended power supply with +12 Volt current rating of 26 Amp Amps.)

Does that mean the card draws 26 Amps (312W)? I'm confused on the whole AMP thing. Surely 26A total for all rails combined woudl be right. In which case I have 30A total for both rails togather.


In the anandtech review of two 8800GTX's (SLI) on a C2D system with two G's of RAM he said it drew 520W total. (makes me think the 500W FSP would be totally fine for one 8800GTS).


And this article makes me feel really good:

http://www.techpowerup.com/reviews/Palit/GeForce8800GTX/13

Even though NVIDIA recommends two power connectors, the power draw of the GeForce 8800 GTX is minimal for this class of card. Basically you get almost double the performance at the same power draw compared to the Radeon X1950 XTX.

Since NVIDIA's GeForce 8800 GTX does not use reduced clocks in 2D mode, the power consumption in 2D and idle is a bit higher though.

Here's a nice quote that makes me feel all warm inside about trying to stick it out with the

500W FSB until I go SLI and get a new PSU:
http://www.nvnews.net/vbulletin/showthread.php?t=80718
8800 GTS works fine on my Fortron 400W psu:

12V1 = 14A
12V2 = 15A

It worked fine on my 7800GT SLI also. The quality and ATX version of the psu is a big factor, make sure it is a ATX 12V ver2.01 or higher. I wouldnt try a 8800 GTX or 8800 GTS SLI on my 400W though.

But all the 2 rail talk in that thread confuses me. One guy is saying one rail is used for the CPU and can't be figured in. In which case my two 15A 12V rails wouldn't be enough.


No idea... I hate wasting money if I don't have to.


If anyone knows the magic answer... will my FSP 500W be OK with a single 8800GTS and a 680i (and an overclocked E6600)?

 

[Bbq]

Jason: It should work alright. If you have an oppertunity to replace it with something beefier, liek a Corsair HX 520, go for it.

Dreven: with a single 8800GTS + 680i, you will be fine. Not with double.

With dual rails: Xbit says about that model you have,

They put a 24-pin connector and declare two +12V rails with, say, 10 and 15amp currents, but also mention that a combined load on both +12V rails cannot exceed 216W or 18 amperes

However, the quality of that model is quite high. you will have no problems.

The guy who says one rail is factored in for the cpu, is right. Assume you have dual 15a rails. The first rail, is dedicated to the CPU. The second rail goes to everything else. Even if the first rail only has 5a load, and the second rail pulls a 14a from everything, Rail #1 will remain at 5a / 15. Max, that is.

 

[TheRapture]

I am using an Antec SP-500 that has 17a and 19a on the rails, it is powering my rig plenty good, voltages rock solid under load. I have a fairly beefy power requirement with 3 SATA drives, 2 dvd-roms, overclocked X2 and overclocked GTS.

I can tell you I "had" a Rosewill 500w that was "rated" at 31a on it's single 12v rail, and it sucked eggs after I got the GTS on there....

Get a good power supply, or be sorry later