Unable to set 2560x1600 on XFX6970 2GB and Samsung 305t

[AceGoober]

Installed a brand new XFX 6970 2GB in rig-in-sig last night using Windows 7 Ultimate 64bit. Latest 11.2 AMD Catylist installed. Previous video card was a Palit GTX 460.

I've Googled for 4+ hours last night and haven't found a solution to my issue.

The max res the drivers will allow me to set is 1280 x 800. Any attempts to set a higher resolution results in a blank screen and the hard drive light blinking every second or so.

The DVI-D connector closest to the video card PCB is verified dual-link. The DVI cable going to the Samsung 305t is verified DVI-D. Had no problems setting 2560 x 1600 on the GTX 460.

Here is what I've done so far:

1. Uninstalled all nVidia drivers,
2. Ran Driver Sweeper to remove residual nVidia drivers and registry entries,
3. Shut down fully,
4. Unplugged power cord,
5. Pressed start button to dissipate any stored electricity,
6. Swapped cards while wearing a grounding bracelet,
7. Powered on system,
8. Booted into Windows at 800 x 600,
9. Installed ATI Catylist 11.2,
10. Rebooted,
11. System performs POST, shows startup, blanks with hard drive light blinking every second,
12. Reset,
13. Booted into Windows @ 640x480,
14. Reinstalled Catylist 11.2,
15. Rebooted,
16. Same issue as # 11,
17. Experimented with resolutions - unable to set higher than 1280 x 800.
18. Ran Windows 7 reference drivers - no change.
19. Swapped-out 6970 for GTX 460 - set res to 2560 x 1600 without issue.

I'm still searching for a solution but thought maybe someone here might know what the solution is for this unusual issue.

Thanks in advance for any assistance.

[antiacid]

out of curiosity, have you considered that maybe your new 6970 is broken? I would recommend testing the 6970 in another system if possible. Also, can you confirm that your PSU is the one in your signature?

Finally, I guess if the card worked in another machine, I'd try booting with a VGA cable instead (possibly to a different monitor, I don't know if the 305t has a vga) and then enabling the 2560x1600 display using the catalyst control panel. I remember having similar issues when I moved to a 4870x3 setup years ago and that had fixed it.

[Dark-Energy]

There's a setting called Reduce DVI Frequency on high-resolution displays in the digital flat panel properties in CCC. Tick it on.

Also, are you sure you are using a Dual link DVI cable? Check this out here

From the moment I set up this monitor, there was something dreadfully wrong; I couldn’t get the darn thing to work at anything above WXGA (1280 x 800) resolutions. Windows Vista would start its boot process and when it was done…BOOM, the monitor would go into the auto-test mode instead of going to the standard Vista desktop. I tried everything from the power cord to the video card to posting on forums about the issue but the one thing I overlooked was the DVI cable that came bundled with the 305T (doh!).

In my blind excitement to get this oversized beast hooked up, I neglected to check what kind of DVI connector Samsung provided with this monitor. I automatically assumed the packaging list’s claim of a dual-link DVI connector was God’s Own truth but once a clearer head prevailed, I took a gander and lo and behold; a single link DVI connector!! I will make this clear right now: the 305T REQUIRES a dual-link DVI cable in order to work at most resolutions. Unfortunately, Samsung packaged a single-link connector with this monitor.

After polling a few of my friends who own the 305T, it seemed that out of the 14 monitors purchased for work and personal use, two (not including mine) had single link DVI cables. What this tells me is that my situation was not an isolated case but after contacting Samsung, they have indicated that anyone with this issue should contact them to have a dual link DVI cable shipped out free of charge.

That being said, for all the tests I have used a Cobalt Cable Ultimate DVI-D Dual Link cable.

http://www.hardwarecanucks.com/forum...-review-5.html

[AceGoober]

Cable I have that came with the monitor is a dual-link DVI-D as verified by continuity checking with a Fluke voltmeter. Even though the cable I had passed I went and bought another in the event mine was acting wierd. Still no change.

Uninstalled all ATI software, shut down, replaced card with my GTX 460, booted-up and after another reboot after the default Windows reference drivers installed I'm sitting back at 2560 x 1600.

I'm done attempting to get this card to work with my LCD. As I type this it is sitting in it's original box ready to ship back to Amazon. A GTX 580 will take it's place. Maybe even a 3GB version if I can find one.