ubuntu 8.04 and vmware workstation 6.04

[Sin]

hi, i am currently running ubuntu 8 LTS in vmware workstation, it works 
well, the problem is that when i increase the resolution in ubuntu to 
1280x1024 , ubuntu becomes slow, it doesnt happen on lower resolution, 
like 800x600.

i thought that this was because of no 3d acceleration in vmware, so i 
enabled the experimental support in vmware
mks.enable3d="TRUE" and also set its vramsize to 64MB

after enabling that, ubuntu became very very slow, even at 800x600 res, 
i even tried to install xserver-xgl package, but still its slow.

Is there a way to increase the performance of ubuntu at high resolutions 
in vmware?