Help! >60Hz Refresh Rate corrupts screen with Gigabyte Radeon X800XT GV-RX80T256V

Hi, everyone.

I bought a Gigabyte X800XT AGP 8X model #GV-RX80T256V used on Ebay (caveat emptor, I know...), and it works fine except when I attempt to change the screen refresh rate to 85 Hz for lower eye strain. When I do, the image on the screen becomes corrupted and unviewable. Every image on the screen; icons, text, and graphics has a slight doubling which obscures it.

The strange thing is, I've used this monitor with an 85 Hz refresh rate with several other cards over the years, and there have been no problems at all. It began when I installed this new card. 60Hz works okay, but is hard on the eyes, and 75 Hz works okay only for 1020x768 which is adequate, but certainly not the best this card can do. FYI, I'm using the latest Catalyst Drivers and software downloaded from Rage3d.com's website, so I know it's not an old driver problem.

Does anyone have any experience with a similar situation? I'm wondering if there is a fix for this somewhere, or a firmware/BIOS upgrade I might need. I've sent an email to Gigabyte, but no response so far...

Any and all thoughts would be appreciated.

Thanks,

Erik.

not heard of that one before.

Have you tried a different resolution at that refresh rate?

My X800XTPE runs beautiful on 75 Mhz but doesnt like 85 either.
75Mhz seems fine to me at any resolution I game at.

you using an extension cable?

IS this on a TFT or a CRT?

No extension cable, but yes it's a CRT.
Rocketeer, I'm intrigued that you can't use 85Hz either. Does 75Hz work at all resolutions?

I haven't had any luck with 75Hz at any resolution other than 1020x768 But I've read somewhere that some folks consider it to be the ideal refresh rate. Personally, I prefer 85Hz, myself.

-Erik