[NTLUG:Discuss] Video problem after memory upgrade

[Douglas Scott]

I have a rather strange problem.  I decided to upgrade my RAM from 512M to 1G.  
I went to Fry's and bought an additional 512M DIMM.  It is the same type as 
the other DIMM, 512M PC3200 DDR.

When I booted the machine back up everything was normal at first until Linux 
actually began to start (that is I could see the BIOS messages just fine).  
Then the screen went blank and stayed blank until KDE started.  KDE was doing 
just fine but I decided to check on why the screen had been blank during 
bootup and so I went to a command line by entering Ctrl-Alt-F1.  The screen 
wasn't blank anymore, it complete garbage.  It looks as though the video was 
completely undefined.  This was definitely not a problem I was expecting.

The machine is duel boot so I booted into Win98SE and didn't see any problems.  
I decided to remove the original DIMM and leave just the new one in to make 
sure that this had nothing to do with the DIMM.  Now everything was just 
fine.  But if I put both DIMMs back in then the problem returned.

I also tried to add mem=1026M to the boot command, but still the same thing.

Looking through the log messages I found the following.

vesafb: abort, cannot ioremap video memory 0x8000000 @ 0xf0000000

Comparing this with messages during a boot boot I see this

vesafb: framebuffer at 0xf0000000, mapped to 0xe080a000, size 131072k
vesafb: mode is 800x600x16, linelength=1600, pages=2
vesafb: protected mode interface info at c000:f0c0
vesafb: scrolling: redraw
vesafb: directcolor: size=0:5:6:5, shift=0:11:5:0
Looking for splash picture.... found (800x600, 25593 bytes).
Console: switching to colour frame buffer device 80x16
fb0: VESA VGA frame buffer device

I also checked in /dev and discovered that /dev/fb0 didn't exist anymore.


-- 
Doug Scott
Arlington, Tx