Hi, After reading yesterdays posts I went home and made some changes to my settings :-

LLC : ENABLED to DISABLED
CPU V : 1.3875 from 1.3275
PLL : 1.56 from 1.50
(VTT was already 1.36)

Before these changes every time I started windows I would get a Norton pop up telling me that my virus definitions were out of date even though they were the latest available. Also, once I had to re-activate it and randomly re-authorise the computer to play my iTunes.

Now it is fixed !! - I made the changes above at the same time so not sure is it is down to LLC or increasing PLL but thanks to Hurin, Slim & RasCas.

Drivers working for me are graphics 177.41 (250+ 3dMarkVantage points) and chipset 9.64 as I can't enable teaming with 15.17.

My rig :QX9770 on Thermalright Ultra 120 Extreme cooler:
EVGA 9800 GX2 SSC. Creative X-Fi Elite Pro.
OCZ 4x1Gb PC3-16000C9 2000Mhz Platinum EB
Samsung F1 1TB & 2X500Gb Hitachi SATA 2.
2xSamsung 20XDVD-RW SATA
Vista Ultimate 32bit

Settings : 430x9.5=4085Mhz overclock. 1720 FSB Syn & Linked.
Mem : 7-7-7-22-30-1T @ 1.9v

Benches : 20,419 3dMark06 7,274 PCMarkVantage.