512M memory and AGP aperture size

512M memory and AGP aperture size

Post by Martin Hofma » Tue, 01 Jun 1999 04:00:00

We have been having problems that are somehow related to the aperture
size setting in the BIOS and the amount of system RAM.  Basically it
seems that the setting for the aperture size must be equal to or
greater than the amount of RAM.  I have found through trial and error
that if the aperture is set to a value below the amount of memory
(eg. aperture 64M and RAM 128M) then I get all sorts of problems, the
machine won't boot or it crashes soon after booting.

I confess that I don't really know what the aperture setting actually
does and whether or not it should have any effect on Linux.  But on 3
or 4 machines recently I have found the same problems occurring.
Fortunately until now I have always managed to set the aperture at or
above the amout of RAM.  However our latest machine has 512M of memory
and the maximum aperture setting is only 256M and in that
configuration it crashes.  Everything works fine with 256M of memory
installed (and the aperture set to 256M).

Does anyone know anything about these problems and is there a way to
fix it so that we can use all 512M of memory?  This latest machine is
a Pentium 300 with the latest Slackware 4.0.0 installation. The video
card is a Viper 550 (Riva TNT) w/ 8M memory.

Any suggestions appreciated,


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Sorry for the crosspost, but I wasn't sure which group was a better
choice.  I have a K7 with a Asus K7M MB.  I got a voodoo3/2000 AGP card,
and since I originally had 128MB RAM, I set the AGP aperture to 64MB (as
someone recommended I do).  Worked fine.  I just upgraded the RAM to 256,
and thought I should keep the aperture at 1/2 RAM, so I tweaked it to
128MB.  System comes up fine as far as the XDM splash screen, then
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