my friend's laptop did not successfully boot and it just keep on restarting after the loading screen appears. The safe mode didn't work either. As well as the installation disk, it get stucked when I press "Repair my computer". And also, when I press F8 and disable "Automatic restart ...... " I faced this error. BSOD: A problem has been detected and windows has been shut down to prevent damage to your computer. DRIVER_IRQL_NOT_LESS_OR_EQUAL If this is the first time you've seen this stop error screen. restart your computer. If this screen appears again, follow these steps:Check to make sure any new hardware or software is properly installed. If this is a new installation, ask your hardware or software manufacturer. for any windows updates you might need. If problem continue, disable or remove any newly install =ed hardware or software. Disable BIOS memory option such as caching or shadowing. If you need to use safe mode to remove or disable components, restart your computer, press F8 to select Advance Startup Options, and then select Safe Mode. Technical Information: *** STOP: 0x000000D1 (0x00000008, 0x0000000A, 0x00000000, 0x839B28D9) *** sisraid4.sys - Address 839B28D9 base at 839AD000, DateStamp 45adcfa2 That actually show up on the screen when I disable Automatic restart.. I don't know what's the cause of this problem, my friend cannot remember the last time he used his laptop. Safe mode and all the options in F8 didn't work either. The installation disk get stucked at Starting set up ( 'cause I want to install new OS on other partition so that I can back up the files hopefully. But suddenly failed. ) I already check the memory using memtes86, no error found, pass only once cause it takes too long. Anyone know this???? Please help.