Thank you very much for trying to helping me. Actually i have download this driver earlier & installed it but there was no success. anyway this morning i have downloaded all the windows updates & installed. but unfortunately there was an update for "Intel HD Graphics" & once after re-starts, the problem starts again & i have ended up with start repair dialog box. it offer me a system restore & once after it finished all the updates has gone.
So again i downloaded windows updates, but this time i cleared the check box for "Intel HD Graphics". once after all install & re-starts problem came again (I disabled the C -state & C2-State in bios Power section before this boot up). this time also i selected Startup repair, but i canceled the system restore it offered & went to the advance options. in the advance recovery options i have done a memory diagnostic & after re-starts.........Boom... it boots up to the windows & there was a Intel HD Graphics as my display adapter.
I don't know what was happend & what is the actual issue was. but i'm suspecting Windows Updates done the trick.
Thanks again for the reply.
Actually i was wrong, the problem was with the C-State & C2-State in Bios power options. So if anybody is having this problem please disable both C-State & C2-State in Bios Power options.
Thanks Sathika for this help.
Actually I was suffering from same problem past 6 months.
Even I had purchased a GeForce 9800TX PCIe Card for display, but it also suffered from same problem.
After disabling C- State and C2-state in bios, the problem solved.
Thanks Thanks Tnahks and many many thanks.