Re: anyone have 'glx' working on 7800 GS OC ??
Don't have much to offer but thought I'd respond just so you might not feel so lonesome out there.
I assume you've done all the usual stuff: latest MB BIOS and drivers and cut off one finger as sacrifice to the Graphic Card Gods. (I'm down to one left to type with.)
Seriously, getting GC fully operational seems to be luck or magic or both. I'm given to believe that Nvidia is better than ATI but neither have the resources to chase down and fix all the Linux issues. Essentially, you're on your own.
I run AMD64 with the 7900GS card. No sweat in WinXP. Major sweat in Linux, especially running a HD projection TV. Tried Fedora 6 for awhile with 9631 then 9746 then 9755 driver. Best results were with 9746. Switched to Ubuntu (6.06) with generally better results. Again, better results with 9746 driver so that's what I'm running now until Ubuntu 7.04 and Fedora 7 hit the street. Then I'll try 9755 (or later) again.
Point is: It sounds like maybe your combination of software/ hardware components may add up to "you can't get there from here".
Perhaps (before you sacrifice too many fingers) you might back up to the 9746 driver. I suspect that 9755 provides little or no utility value to the operation of your card or mine.
You might also consider another distro. Yep, it's a couple of hours of effort but it might give you better results. Might also give you more insight into your problem if you see how another distro handles your card.
Good luck with it.