Comment 36 for bug 1049630

Revision history for this message
In , axel (simon-simonfoley) wrote :

Hi Brian,
       I have been a bit quiet on this bug because of work commitments. I too flashed my Packard Bell dot ma with the Gateway v1.3302 BIOS (Although I have lost VT support which is a pain)

I initially achieved graphics stability by changing the UMA+Sideport to just UMA in the Advanced Northbridge Options.

In Sideport only Mode it indicates that there is only 64MB of video memory and when I try to boot with sideport only the laptop hangs on boot.

Have you tried the following?

Internal Video Mode: UMA+Sideport
Video Memory: Auto
Dual Mode Interleaving: Enabled
Dual Mode Non-Interleaving SP Size: 0MB
Dual Mode Interleav Ratio: 1:7

In theory this should allocate 512 MB of video ram (UMA=448 + 64 Sideport)
Ratio of 1x64 Sideport to 7x64 UMA.
If you look up the specs of the RS690 this is its theoretical MAX addressable memory and so they back each other up.

http://en.wikipedia.org/wiki/Comparison_of_AMD_graphics_processing_units

As such it suggest that the main BIOS Page is incorrect in reporting 384 MB
video RAM (256MB Max UMA + 128MB Sideport) as Sideport is probably only 64MB as reported accurately by the "Advance NB Options Page". Also note if Main page of the BIOS is correct why when you set the UMA Memory manually to e.g. 32MB does the value reported in that page not drop ?

It all looks to me like sideport is only 64MB.

Since I have been running the settings above I cannot recreate the problem
with UMA+Sideport and Graphics performance has massively improved. I can now play iPlayer full screen with the standard un-accelerated ati driver.

>> I would like somebody else to test these settings because I suspect that
I may not be seeing the corruption because Unity has defaulted to 2d mode regardless of what I choose on the login screen.

For those that want the background as to what these BIOS options mean see the link below;
http://www.tomshardware.co.uk/forum/322592-15-difference-sideport-mode

I will also attach some BIOS Developers guides for the chipsets for reference