Hey guys, I bought a 2nd hand XFX 6870 from someone who bought it but did not have the dual power connectors to wield it. There were not screw marks displaying signs so I'll give him benefit of the doubt. I believe my culprit is my weak PSU:
CPU: Phenom ii x4 970 Deneb 3.5 ghz
Mobo: Biostar A880G+ Micro ATX
Ram: 2x 4GB G. Skill RipJaw 1333 (compatible with board)
PSU: Thermaltake 600w 20/24 pin power connector type (3 egg review on newegg)
5 120 mm LED Fans
2 90mm LED Fans (one pointing straight at my vid card)
HDD: 250 GB WD, 500GB Seagate Barracuda, 2x WD Raptors in raid 0
On ExtremePSUcalculator I'm hitting an estimated 578 watts. My Sapphire 6850 works just fine until I overclock past 925/1130 1.20v and have my CPU at 4000. That's when "driver not responding" begins to happen. When I scale my CPU back I can play just fine at those settings on my 6850.
What's your opinion on my 6870 artifacting at stock settings? This happens in regular windows display as well as games. Did not begin to happen until I ran a few bench tests 30 min afterwards.
If the card is giving you artifacts at stock settings then it can be one of two things.
1. The power supply is defective and not giving you enough power to run the card.
2. The video card is defective.
while thermaltake does make crap PSUs that system would not pull anywhere near 578 Watts.
I'd say the card is bad since you 6850 does fine overclocked and the 6870 artifacts in windows, and the guy who sold it to you probably knew. Not sure what you do to your cards to get "screw marks". Can't imagine why ud buy a 6870 if you had a 6850.
It doesn't have an 80 bronze cert and the max output is showing 576 with a total of 600w which if I assume I'm reading it right, puts me at a little below what I'm actually trying to get out of it. I've also heard this PSU to be a bit shady with it's connector tolerance. Has anybody ever used this PSU before? According to the estimate my system actually pulls roughly that amount when everything is OC'ed and the PUS itself is about 4 years old.
Are you sure you can even crossfire a 6850 and a 6870?
Even so, you are going to need to up your PSU to crossfire. Dual cards = double power consumption.
Also, when I was having artifacts with my 6870, I RMA'd it and was still getting Artifacts with the new card. I then swapped out my BFG 550w PSU for an LSP 650w PSU and haven't had the artifacts since.
Areamike, I read up on your past thread and that's what mainly gave me the idea of a PSU problem. I am able to crossfire any 68xx series together (if your talking about my mobo, I'll be upgrading that soon as well). Thanks for your incite Mike, I believe my PSU has nearly the same wattage as your old one, yet mine has the flaws (from other party references) and is not certified for 80 (they remade another version of this one later on to make up for it).
I'll be trying another PSU as soon as I can get my hands on one, I'll probably get one at Best Buy to try it out and then return it for my preferred choice if it is the culprit. I still have the choice of RMA I believe because I am the first one who registered the card officially.
4/9/12 Update: I received an RMA code from XFX and have shipped off the GPU, if the problem is consistent with a new one I will be trying a new PSU. They have very good and fast technical support from my experience SO FAR.