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DVI Flicker During POST Bootup

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bladephoenix

Senior member
I am using a Viewsonic VP201s on a ATI AIW Radeon 8500 (Yes I know it is a somewhat obsolete card for the monitor, but I cannot afford to get a new card yet).

The problem is that when I start up the computer into POST, the screen flickers like crazy...there is not even a way to describe it...it's like pure television static. The problem continues all the way into the Windows 2000 startup...and it continues even then. All the way until I reduce the screen resolution to 1024 to 768. At 1600x1200 is flickers like crazy. At 1280 x 1024, it is reduced marginally - but only if I increase the refresh rate to 85 Hz. I know the problem is not with the monitor, as I have tried two of them so far...both with the same problem. I am guessing it is probably the video card or the mobo. I have tinkered a bit with BIOS settings to no avail.

Has anyone had this problem? Any help would be appreciated...in fact, I can say with certainty that you would be a personal hero to me should you do so - though that may or may not be a good thing =)

Thanks in advance!
 
OK...I seem to have fixed a little of the problem. I went under the Display Properties, Advanced, Options, and checked "Reduce DVI Frequency on High Res Displays". That seemed to virtually eliminate all flicker at 1600x1200 resolution. I guess Radeon cards tend to send too much information for a 1600x1200 DVI to handle.

Now that the problem is eliminated in Windows, I just need to find a way to fix it in POST / BIOS (Before any video driver is loaded). Under the Viewsonic OSD, I have found out that the resolution of the monitor at bootup is 1600x1199 (pretty close to 1600x1200).

I am guessing that the monitor (when in DVI mode), tells the video card its native resolution at bootup. The video card in turn, sends all the pixel information for 1600x1200. The problem is that the video card sends the information at a frequency too high for the monitor to handle. However, once windows (and the ATI drivers) load, the driver tells the video card to reduce its frequency, thereby eliminating the problem at that point.

Because the native resolution of the DFP is hard coded, there is no way to change the resolution of the monitor at bootup. The monitor simply tells the ATI card its native resolution and the ATI card starts at that.

The problem then is how do I reduce the frequency of the video card at POST/boot?
 
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