Thanks for the input,some period of time it just hung up..put a big fan again on top of the heatsink of processor which I think also it's a heat related issue.Install Norton and scan for virus (no virus detected)and used norton utilities to check my computer,let system on and about the following day system won't turn again...wait for acouple of hours to back again..then decided to check all the driver and first update the Video graphics (S3-Twister)..so far still running after updating the video..will just let it on again overnight..will update what will be the outcome...thnks again for the input