nvidia-96 drivers causing garbled text, display on Geforce 4600

[Sayantan Das]

I have a sony vaio desktop (PCV RZ221) which runs windows xp. I installed ubuntu on a separate partition. The install runs fine but the graphics runs on fallback drivers even though it has a nvidia geforce ti 4660 graphics card installed. I have tried installing the nvidia drivers (nvidia-96) which were recommended by the 'Additional Drivers' application. This results in complete garbled text and video. Everything turns white once I restart the system after installing the nvidia drivers. The nouveau drivers do not work etiher.
I have tried three different versions of ubuntu (10.10, 11.04 and 11.10) and all of them have the same issue.

Below is the technical information of the motherborad

Technical Platform
Architecture
SiS 651
CPU Section
Processor Name
Intel® Pentium® 4 processor
Processor Manufacturer
Intel
Processor Speed (Mhz)
3060
Model
3.06 Ghz
Type
Pentium IV
L2 Cache (kb)
512
Graphics
Graphic Card Name
nVidia GeForce4 TI4600
Total Graphics Memory (MB)
128