I know that I'm posting to a very old thread, but here goes:
EVGA NVIDIA 680i SLI mobo
Intel Core 2 Duo E6600, OC from stock 2.4 to 3.2 GHz, 1.4v (very stable under any stress load I throw at it)
EVGA 8800 GTS (no voltage tweaks, it seems to be 1.300v stock)
650 watt Antec TruePower Trio (three 12volt power rails)
Windows 7 Ultimate 64-bit
I'm using newest OC utilities from EVGA and they work super.
http://www.evga.com/support/download/default.aspx to download :
(Get both)
1) EVGA Precision (or just "Precision") (released 2 Sept. 2011)
2) EVGA OC Scanner (or just "OC" or "OC Scanner") (released 9 August 2011)
Just d/l and install.
Now, run Precision, set Core Clock, Shader Clock (or just leave "linked" to
Core Clock and let it adjust up or down with adjustments to Core Clock),
Memory Clock, and Fan Speed.
Then click on "Apply", then "Test".
Clicking on "Test" will make OC Scanner pop up
With OC Scanner you'll see a ton of info:
The core, shader, memory, and volts, GPU temp, load, and fan.
(I've noticed the fan speed is more accurately depicted on Precision than OC Scanner,
so I keep an eye on it there.)
Also has "GPU Stress Test" button which brings up a window that puts a pretty
good load on your GPU (you can adjust the size of this window to just about any preset,
or use "Custom" or just plain "Fullscreen"
Here's what I tried so far:
Core Shader Memory Fan speed Load temp (normally runs at 56 to 58C without load.)
675 1563 (linked) 910 100% 74C Seems to run pretty stable (no screen flashing or artifacts)
While on the subject of artifacts, keep an eye on your gadgets in the sidebar, they will
start flashing, ripping, and other carrying on quicker than anywhere else on the screen.
(That means it's time to reduce some settings in Precision)
Then I tried:
675 core, 1563 (linked)shader, 925 mem., 100% fan, ~75C load temp. At about 45 seconds I got video flashing, major artifacts,
and finally complete black screen (video drivers did not reset as usual after a crash (had to re-boot computer)
That was just with a fairly minor memory OC (from 910 to 925)!
Dropped back to 650 core, 1505 shader (linked), 825 memory, and 100% fan.
Seems very stable but temp climbed to 80C for some reason.
A white paper on 8800 GTS I read a while back stated that 105C is the absolute maximum temp., so never
approach it closely (I'd say about 95C max) or exceed it under any circumstances.
So, somewhere around 675 core, 1563 shader, 900 memory, 100% fan is close to the max I can get out of my 8800 GTS, as configured.
There are no BIOS settings changed, just stock for video voltage and some other video settings that can be changed.
Anyway, that's about my 2 cents worth.
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