Help troubleshooting UT3 shutdowns!!!

I play mostly UT3 these days and recently i got this annoying problem where after about half an hour sometimes an hours playing the game suddenly crashes mid-play.

Iam using the latest WHQL drivers 182.08.

My Ultra is slightly OCd and peak temps are less than 90c which is very good for an Ultra I think. (recently got a new PCI slot cooler for it)

My CPU is OCed an peak temps are 65c with P95.

RAM is Not OCd

I looked in Problems reports and Solutions an the following is the error report for UT3.

Description
A problem caused this program to stop interacting with Windows.

Problem signature
Problem Event Name:AppHangB1
Application Name:UT3.exe
Application Version:0.0.0.0
Application Timestamp:48918540
Hang Signature:9cdd
Hang Type:2048
OS Version:6.0.6001.2.1.0.256.1
Locale ID:1033
Additional Hang Signature 1:58716be464dca91f8e7e94f384ddfcdb
Additional Hang Signature 2:6ff6
Additional Hang Signature 3:eacae13fceb07efeed78155e77b95bd2
Additional Hang Signature 4:9cdd
Additional Hang Signature 5:58716be464dca91f8e7e94f384ddfcdb
Additional Hang Signature 6:6ff6
Additional Hang Signature 7:eacae13fceb07efeed78155e77b95bd2

can anyone make heads or tails ouuta this?

Before anyone asks I played Crysis and no crashes so far, but I really don't play it as long as UT3.

Any help would be highly appreciated an repped.
Thanks
SWLS