ctd problems!

Hi all, new to the forums but have been simming for years:)I got the md 11x a few days ago and I'm really enjoying it, but every now and then I'll get a CTD! I own a i7 330"overclocked to 3.2,windows,vista 64bit,gtx470 and 6 gigs of ddr3 ram.These are some of my error reports:Problem Event Name: APPCRASHApplication Name: fsx.exeApplication Version: 10.0.61637.0Application Timestamp: 46fadb14Fault Module Name: TCAS2v7.dllFault Module Version: 1.1.6.0Fault Module Timestamp: 4633aecdException Code: c0000005Exception Offset: 00006186OS Version: 6.0.6002.2.2.0.768.3Locale ID: 4105Problem Event Name: APPCRASHApplication Name: fsx.exeApplication Version: 10.0.61637.0Application Timestamp: 46fadb14Fault Module Name: d3d9.dllFault Module Version: 1.0.0.1Fault Module Timestamp: 48751493Exception Code: c0000005Exception Offset: 00006d1cOS Version: 6.0.6002.2.2.0.768.3Locale ID: 4105Extra information about the problemLCID: 4105Problem Event Name: APPCRASHApplication Name: fsx.exeApplication Version: 10.0.61637.0Application Timestamp: 46fadb14Fault Module Name: PMDG_MD11.DLLFault Module Version: 10.0.61355.62Fault Module Timestamp: 49b7c81dException Code: c0000005Exception Offset: 00118301OS Version: 6.0.6002.2.2.0.768.3Locale ID: 4105Extra information about the problemLCID: 4105any ideas would be great thx,Sixxer