Probable bad cpu or mb? maybe memory?


Feb 25, 2010
Need help please..

My wife was using the firefox internet just browsing when she got a BSOD, then follow by a black screen with blinking _ at the top left side of the screen.

Now when i turn the computer off, i get past the post and then followed by the blinking _ at the top left screen. Then nothing happens.

It's been working flawless for about 5 months since I built it up.

Attempted fix were:
loaded default bios -- still the same.
tried to load bootable dos usb drive to check memtest -- same won't boot past the blinking _.
unplugged hard drive and any disk drive -- same.
removed 1 stick of memory - same. the other memory same.
replaced with a new psu - same.
replaced a working guaranteed videocard - same.

everything hardware looks like it's normal and temps from the mb just stays at 38C.

core i5 750 - HS is Thermalright ultra 120
evga p55 le
ocz 1333 ddr3
xfx 5850
500w ultra xfinity psu
seagate barracuda 320gb

I don't have any other parts laying around to replace the memory, cpu or motherboard. So those 3 I can't rule out which one..
Does anyone have any experience with the same symptoms as this?


Aug 15, 2006
i think u must reinstall your operating system. maybe some files have been corrupted or a virus. secondly have u tried to wait when that blinking happened. like switch on your computer and when the blinking comes, just wait. maybe after sometime it goes ahead. u can also do is that go in the bios and then go to the boot priority side and set the hdd to boot first then any other hardware. maybe that helps. hope i helped.


Feb 25, 2010
Yes, it is a blinking cursor of _ nothing else on screen.

I tried changing boot device priority in the bios to boot my usb to check my memory but it just wont get past that blinking cursor. Even if there's no hard drive plugged in, it won't get past that screen and say bad os or something. I waited it out before more than 10 minutes also and still the same.