I've had my Gigabyte 6850 for over a year now but only recently tried tweaking it to get better FPS in the newer games. However, it always freezes up and says the card has crashed even when only using AMD overdrive settings. Did I get a lemon?
My system is a AMD Phenom FX OC'd to 3GHZ, 8GB ram, 800W Inwin PSU.
Did you try adding a bit of voltage? The smallest that you can just to see it it would prevent the freeze up. If that doesn't work then you may need to try another overclocking program. MSI Afterburner is one that you could try.
I have tried to use both trix and msi software but always the tabs or options for voltage adjustment are unusable or greyed out. I have tried to edit the cfg file on msi afterburner but system won't let me.
I just took my Sapphire 6850 to 980 / 1190 stable with no artifacts on stock voltage using Trixx. Download the newest one, it added in overvolting. Just be very careful. Also what are you temps @ idle & load?
Just read that this particular Gigabyte model does not support voltage control. Very underhanded move by gigabyte considering I based my decision to buy this particular product based on an overclocking review I read.