Quote Originally Posted by STE\/E View Post
Yeah it's gotta be the User, what would any of us know about Video Cards ...
Steve, I wasn't making a comment on your knowledge of GPUs, I was stating what my experience has been with 5970s. If the card won't get to 850 then there is a problem somewhere ... either the card is defective -or- possibly you need to run the benchmark on that machine and see if it shows "core 0' as the fastest since that is what the automatic selection is choosing for that machine. I had 2 identical machines (dual Xeon servers) that I started running my 5970s in. On 1 machine Moo was fastest on Core 0 and on the other machine it liked Core 3. They both produced the same credits but required a different "core" setting.

My experience with 5970s involves 6 cards. The original 2 failed and were replaced, which eventually failed and were replaced, which eventually failed! The last time XFX replaced 1 with a 6990. I haven't sent in the other 5970 yet but it has also failed. All failures have either been the fan crapping out or GPU 0 throwing artifacts and slowing down where even clocking at 700 wasn't reliable.

On heating ... whatever engineer did the vapor chamber design on the refernce design cost AMD and the vendors BIG bucks. The VRMs for GPU0 are NOT under the vapor chamber and run extremely hot. Those are what limits the OC ability of the card. The temperatures that need to be monitored (GPU-Z) are not the "GPU" temp but the bottom 4 that are shown down at the bottom which are the VRM temps. On GPU 0, the card may be report the GPU temp as 75C but the VRM on GPU 0 may be pushing well over 100C. At 120C the card goes into a self protection mode and starts slowing down the clock.

If the GPU 0 graphics chip starts crapping out you will usually see it in the current being drawn (GPU-Z). Running Moo/MW at 850-900 MHz the chip should draw around 65A but if the chip is having trouble then you will see currents in the 90-95A range. A standard 5870 also draws around 65A when running at 900 MHz.

BTW, the 5970 is NOT two 5850 chips even though they state it is like a dual 5850. According to an AMD interview when the card 1st came out it was designed to be a dual 5870 and it uses the same chips. The problem according to AMD was that when clocked to 5870 levels it exceeded the power specs for a single PCIe slot. It exceeded BOTH the total power spec (300W) and the power required from the MB (75W). That is why the refernce design came out with something like 1.0V on the Vcore ... that limited the power draw to keep it within the PCIe specification. Prior to introduction AMD put out a program (that got pulled before introduction) that allowed the user to raise the Vcore and memory voltages above the stock level. Most vendor did suppy that utility with their cards ... XFX called their version of the program Overvolt.

The bottom line is with the experience I've had with my 5970s I had decided that I would NEVER purchase another dual card. With what I've seen with the 6990 it would be stupid to not purchase another. They have totally fixed the problems that I saw in my XFX 5970s.