HIS HD3850 IceQ3 Turbo (AGP) PROBLEM

Hello,

I have extremely irritating problem on this card: it crashes in every game I play and messed up textures appear! Card is not overclocked (720/1820). This seems like a memory problem, so I tried lower its speed. And guess what! NOTHING! Same crashes occur! It doesn't matter whether mem is set to 2000MHz or 1500MHz. In ATI Tool artifact scan utility card can work well for hours, but neither 3DM06 nor games run properly. I've tried all AGP hotfix drivers, then flashed card so that I would be able to use official ones, but nothing helps. Also set AGP speed to 66MHz and and tried out other possible moves. I have never experienced anything similar with Radeon 9800PRO, 9800XT, GF6800GT, 6800Ultra, 7800GS, 7950GT.

My PC:
ASUS P4C800 Deluxe board (875);
P4 EE HT @ 4.0 GHz CPU;
2GB Kingston HyperX 500MHz CL2 memory;
2 x 1.5TB HDD at RAID;
HIS HD3850 AGP IceQ3.
500W PSU 2.0 with direct 8 pin PCI-E 2.0 cord.

Other overclockers push this card to 2ghz on mem stable, so I'm starting to think it has a FAULTY MEMORY. Unfortunately I'm not able to return it back to seller because I bought card from Hong Kong and sending it back and receiving again will cost me ~110$, which I cannot afford.
Has anybody experienced similar memory problem? Any help will be very appreciated. Thank You.

I have the same card, except for it's the PCI-e version. It's possible that it's overheating, since the fan stays at a low speed, no matter the load on the card. You can try to increase the fan speed using RivaTuner or another fan-controlling program.

Unfortunately it's not an overheating problem ;/. I've been keeping fan fixed at 90% since I bought it. bdcrlsn, what is your max memory overclock?

Haven't you had stability problems with it? I mean texture mess up or signal loss?