GMA 950 stuck at 1024 x 768

[bhp666]

I have installed iPC 10.5.6 with no trouble except the video is stuck @ 1024 x 768
hoping to get it to 1280 x 1024.

hardware:
Intel board -BOXD945GCLF2
ATOM 330
North Bridge Intel 945GC
South Bridge Intel ICH7
Onboard Video Chipset Intel GMA 950

Samsung LCD SyncMaster 931bf using VGA connection

This is my first install, 95% working - from i read, i should count myself lucky.

other issue is i need the dvd to boot and no sound, but those can wait.

There seems to be lots of information out there for these issues i am having, but most take for granted that i know what they are referring to.
I am a TOTAL OS X newbie.
All my experiences are Linux and MS.
Not afraid to get in there, but not sure where that is.

Specific direction needed - thanks very much.