It is currently Tue Sep 30, 2014 12:46 pm

All times are UTC - 8 hours




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: power requirements for 8800 series under load?
PostPosted: Mon Nov 10, 2008 7:53 am 
Offline

Joined: Wed Oct 29, 2003 5:55 pm
Posts: 82
Vijay's blog mentions power requirements for 8800 series cards running the GPU client:

Quote:
We've been told that 8800's require 600W power supplies, but we're finding that even a little bigger (eg at least 650W) is important to leave some room for error. We are working to see if there is some way to detect this issue in software, but for now, if you're getting EUE's on the NV GPU client, this is something to consider.


This is news to me. I've run the client on my 8800GT using a Neo HE 430 PSU, and the only problem evident to me is the whine from the video card. Can anyone clarify, debunk or otherwise expand on this?


Top
 Profile  
 
 Post subject:
PostPosted: Mon Nov 10, 2008 12:24 pm 
Offline

Joined: Sun Dec 09, 2007 1:19 am
Posts: 104
Location: Moscow, Russia
The GPUs' Thermal Design Power is from 105 W (8800 GT, probably less for 8800 GS) to 185 W (8800 Ultra). NVidia apparently recommends a 450 W power supply for a GeForce 8800 GTX.

The blog says that "this core had code optimizations that drove the GPU so hard that it would draw a lot more electricity", but I wonder if nVidia's way of calculating TDP permits stressing the GPU beyond it.

_________________
Spring 2008 build with upgrade. Intel Core 2 Duo E8200, Scythe Ninja B w/Slipstream @ ~ 700-960 (too high), Gigabyte GA-P35-DS4, 2x2 GB DDR2-800 CL5 Samsung, nVidia GeForce 9800GT 55 nm, AC Accelero S1 passive; WD Caviar GP 1st gen 500 GB, Pioneer DVR-215D; Antec P182, Antec Neo HE 430W, 2x Scythe S-Flex 800 top and back exhaust, 1x on middle HDD cage. CPU 27, 45; GPU 41, 56


Top
 Profile  
 
 Post subject:
PostPosted: Mon Nov 10, 2008 1:25 pm 
Offline

Joined: Mon Apr 25, 2005 10:00 am
Posts: 2131
Location: Grand Rapids, MI
Check my sig.

I'm running a 8800GT on a Earthwatts 430W and while the fan ramps up, it's because of the temperature not the load. I'm pretty sure I wouldn't have a problem running my gaming system with my Seasonic S12-330, but that's happy in my HTPC.

_________________
HTPC: OrigenAE X11|Gigabyte GA-MA785GPMT-UD2H|Phenom II x3 740BE w/AC Freezer 7|150GB Velociraptor|Corsair VX450
Main: Antec 300 (SlipStream @ 800rpm/140mm @ 5v)|Asus M4A88TD-M|Phenom II x4 945 (Mugen2 pass.)|Asus EAH6850|Samsung 830 128GB|Antec TP750
WHS: DF-85|P8H67-M Pro|I5-3450S/Hyper 212+|Corsair AX650|Sandisk Extreme 240GB, 2xWD20EARS, 2x WD15EARS, WD15EADS


Top
 Profile  
 
 Post subject:
PostPosted: Mon Nov 10, 2008 2:11 pm 
Offline
Friend of SPCR

Joined: Wed Jan 16, 2008 8:56 pm
Posts: 356
Location: Council Bluffs, Iowa
The power supply recommendations on video cards are based on the power supply ratings provided by the manufacturers of the $5 power supplies bundled with computer cases. Various white-box, stamped-steel units are...optimistically rated, and are liable to release the magic smoke or even catch fire if they're asked to deliver anything near their rated load for more than a few seconds. To get around this issue, video card manufacturers routinely recommend a power supply with roughly five times the required capacity.

A high-quality power supply actually will deliver rated capacity for extended periods of time. Conveniently, pretty much all cheap power supplies are also loud, so anything suitable for an SPCR computer is going to be pretty capable. If you've got a proper power supply, then you'll be pleased to know that, in normal usage, an 8800 GT won't draw more than 80 watts, and even the mighty 8800 Ultra can only burn through 140 watts. This might go up for Folding, but I doubt it'll even hit the TDP mentioned in an earlier post. Most 8800 users, even those with an Ultra and a quad-core, would be just fine with a 300-watt PSU. Even a money-no-object overclocked quad core/SLI insane computer will struggle to pull 600 watts.


Top
 Profile  
 
 Post subject:
PostPosted: Sat Nov 15, 2008 7:56 pm 
Offline
*Lifetime Patron*

Joined: Fri Apr 04, 2003 6:21 pm
Posts: 4247
Location: Undisclosed but sober in US
http://foldingforum.org/viewtopic.php?f=52&t=4709

_________________
People who put money and political ideology ahead of truth and ethics are neither´╗┐ patriots nor human beings.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Nov 20, 2008 1:02 am 
Offline
Patron of SPCR

Joined: Wed Apr 18, 2007 12:55 pm
Posts: 47
I'm running 2 x 8800GT 256MB @ 719core/750mem (each passively cooled by an accelero s2) and a Q6600@2GHz@0.9v all off an Enermax 385 Pro 82+. The total power draw under load (2 x GPU2 and 3 of the Q6600 cores assigned to SMP) is ~225w. This figure may go up a bit with the newer more intensive WUs but I haven't checked the draw recently.
So, in my experience, an 11,000ppd machine really doesn't need anything more than a quality ~400w PSU.

As for the GPU whine, a little bit of blu-tack on the GPU's "no PCI-E power cable" speaker reduces the squealing noise substantially.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 8 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group