VGA Problem about 440bx chipset

Richard Smith rsmith at
Wed Sep 1 09:48:00 CEST 2004

Chiu Gerald wrote:

> you mean that PCI card works?

Yes some PCI cards work.  I've made several Assiliant 65550 and 69000
based PCI cards work and some S3 based cards work.  There are reports of
some ATI cards working but I am still having problems getting my ATI M1
based card to work.

> Now I changed to a PCI video card,and bochs had run the vga bios,but 
> still nothing happened!

> I have no idea what should I do next.

Are you setting up the shadowing correctly?  You have to setup the
shadowing in loader.s or bochs and the video bios never make it into
ram.  The stock ADLO setup won't work on the 440bx.

I've attached my loader.s which sets up the shadowing correctly.

Also the DEBUG_SERIAL option in rombios.c is very useful.  You can
enable it and all the bochs bios messages will be redirected out the
serial port.  This way you can see if bochs rombios is even getting
called.  You have to turn it back off to get text on the VGA screen.
But your cards VSYNC should happen regardless. (assuming the vbios runs

I leave in a few hours and won't be back till Tuesday the 2nd so you are
on your own for a few days.  I'll try to check email during that time
but I'm not promising anything.

Search the mailing list for things like "ADLO", "vgabios", etc there are
several threads on getting this up.

-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: loader.s
URL: <>

More information about the coreboot mailing list