Whocrashed reported (for crashes both with Asus and now with Sapphire) either ntoskrnl.exe (WHEA_UNCORRECTABLE_ERROR), or problems with atikmpag.sys.
Now for the recent update:
The HDD I have is divided to two partitions: 80GB for system, rest for the data.
I have run Windows chkdsk first for the system partition - it went fine without any problems.
When I booted Windows, I have run the chkdsk from the GUI for the data partition (this did not require rescheduling after the restart - there are no system files on the data partition), but I did check "Fix errors on the volume", so it was taking a long time.
After couple of hours, I went to a crashed system - no BSOD, but corrupted graphics (like divided to 40 or so small tiles, accompanied with graphical artifacts and shimmerings.
After restart, the BIOS did not locate any SATA devices (this HDD and DVD/RW drive).
I disabled SATA controller in the BIOS, turned the PC off and after that unplugged from the power.
After that I plugged it back to power, turned it back on, enabled SATA controller in the BIOS and was able to boot to Windows.
I am now running the chkdsk from the command prompt again to see if it fails again.
A bad HDD? Or bad SATA controller (bad motherboard?)?
Please help detecting HW(?) issue.
CPU: intel core 2 duo 8400
former GPU: Asus ATI HD4850
new GPU: Sapphire HD7770
MB: MSI P35 Neo2
System is not overclocked, and never was.
A short history of the problem:
about a month ago, I experienced a BSOD playing Borderlands 2.
After restart I tried it again, got the crash within few minutes. After this, the card started showing artifacts and the windows would not even boot.
Next day, I was able to boot windows, but got the crash within GPU benchmark. After that, card was showing artifacts even in BIOS.
I suspected faulty graphics, so I bought a new one.
To my surprise, it started crashing the system just as before (BSOD), reporting either hardware error, or atikpmg.
I suspected drivers. Performed clean install of the system (Windows 7 64-bit).
I tried 13.12, and 13.9 and 13.4 drivers. No change in the behavior.
The problem is not limited to Borderlands 2, I tried X-Com Enemy Within (not really resource-hungry game). It crashes within 10 to 40 minutes.
Problem is that I can not reproduce the crash with any benchmarks.
I run memtest (bootable USB) for 4 hours. No errors.
I tried Prime95 and Intelburn for CPU test: no errors.
I tried Cinebench, Furmark, OCCTPT and "Video card stability test".
I also tried the OCCTPT and IntelBurn running together. No errors, no crashes.
I even ran HDD check. I ran OCCTPT power supply stress test.
I GOT NO ERRORS IN ANY OF THIS.
I really do not understand what is happening nor how to proceed.
Please help.

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