I recently began upgrading components on my Dell Dimension E521 system. I purchased a Sapphire Radeon HD 5570 video card to replace my ATI Radeon X1330 card.
I run Windows 7 64bit at a screen resolution of 1920x1080 @ 60Hz. The X1330 had no issues with this resolution. After I installed the HD 5570, I discovered that resolutions higher than 1280x1024 @ 60Hz would cause the screen to turn on and off -- not flicker exactly, but "show the screen for 2 seconds, show blank screen for 5 seconds, show screen for 3 seconds, show blank screen for 12 seconds..." There was no discernible pattern, and the screen would never stay "locked."
I thought this might be a power issue, so I replaced my stock 305W PSU with a Corsair 450W PSU. It did not solve the problem.
I have installed the 10.10 ATI driver -- did not solve problem.
I uninstalled the 10.10 ATI driver and tried the 10.3 ATI driver (from forum suggestion) -- did not solve the problem.
The card works correctly at any resolution under 1280x1024 @ 60Hz. Does anyone know what could be causing this issue?
Dell Dimension E521
AMD Athlon X2 4200+
ATI Sapphire Radeon HD 5570
Interestingly, the problem has been solved... somewhat.
I changed the video cable from the card to the monitor. I was using a standard DVI-D cable. I replaced it with a VGA cable. Afterwards, 1920x1080@60Hz was not a problem. The screen is crisp and clean.
I don't know whether the DVI-D cable is faulty or the DVI-D connector on the video card is faulty. Perhaps neither; I don't have another monitor to test it out. Does anyone know what might cause a DVI-D cable to operate correctly up to a certain resolution and then fail at a higher resolution?