GPU Power Consumption

[bergy690]

I have a ASUS GTX 980 Strix as my GPU in my gaming PC, and I've been debating buying another 980 for SLI. The ASUS page says "up to 300Wadditional 6+8 pin PCIe power required". On the 12V rail that corresponds to ~25A. At the local Fry's Electronics, I was told that each of the Strix 980s wants 300W and 30A.

However, when I connect my system to a Kill-a-watt meter, I find that at idle my PSU draws 180-200W from the wall (155-161W, PSU is 80+ Bronze). When running Unigine Valley for 10 minutes, I find that the PSU draw is 340-360W (287-298W system draw).

My system uses an ASUS M5A99FX PRO R2.0, an AMD FX-8320 OC'd to 4.5GHz, Corsair H100i, and various minor components. As such, you can see my surprise at the wattages I gave above; they all are surprisingly low. These would seem to indicate that the Strix 980 does not draw anywhere NEAR 300W even at full load.

Does anyone know (from first-hand experience or otherwise) how much power the Strix 980 draws? I've read various reviews and various ways to estimate component wattage draw, even one method describing how to use a few hundred dollar oscilloscope to determine wattage. I get too much conflicting data to know for sure what to believe...

 

[Petrossa]

Howdy.
While not for the exact model you have, perhaps this except from an article will help you:
http://www.tomshardware.com/reviews/asus-matrix-platinum-geforce-gtx-980,4061-3.html

 

[i7Baby]

See http://www.guru3d.com/articles-pages/asus-geforce-gtx-980-strix-review,7.html 190W

RealHardTech recommends 520W for a PC with one 980 and 750W for a PC with 2 980s.

These recommendations usually leave 300W for everything but the GPUs.

Any PSU you you use should be good quality including having a single 12V rail. This way the amperage takes care of itself.

 

[makkem]

Hi
Just a note.
The Kill-A Watt meter is not a very good method of measuring GPU power as the meter has a relatively slow sample rate so only gives an average while the GPU tends to draw power in rapid peaks and the PSU has to be able to supply the power during those peaks so needs to be of a higher rating than the meter would suggest.

 

[bergy690]

Sorry for the long response time. Is there a wattage meter I could use, shy of some crazy expensive oscilloscope? All the reviews I read, like OC3D, Guru3D, Hexus.net, HardwareCanucks, etc. say that the entire system draws (at most) 400W from the wall. This would seem to imply that running 2 Strix 980s would not require a 1000W PSU with 4x 12v rails at 40A (exaggeration, but you get the point). Thanks for the help!