So, i guess you have a problem with your browser (firefox)...
Try re-install it or update it with the latest version, your system is fine.
thanx for reply. I tried but nothing happend. I had change my fire fox and operating system too. I just want to know "is it a hardware problem or direct x 10.0 problem. When i install direct x 10 my fire fox getting problem on startup the firefox. and i was fix it up with change a file name that a forum tell me & it was fixed..
My another problem is that i had unlock my amd phenom 555 be(x4 B55 3.2Ghz) with stock cooler. my cpu temp. is 54C and in load ~62C. So i want to buy a cooler master 212 plus. please tell me is it help me or not.
THANX FOR YOU COPRATION.