Computer stuck at black screen with flashing white underscore

IzalithFuror · 21 Oct 2012

Today I started up my pc and after the BIOS screen (the place where you can press f8-f11 for various options) it went to a black screen with a blinking underscore in the upper left corner and stayed there indefinitely. It did this even after reboot.

I tried using the diagnostic tool and everything it tested passed (including HDD). I did this test twice and the same results were produced.

I also googled for similar problems (one topic mentioned that the op disassembling his computer and physically tapping a chip on the motherboard caused it to work) but I have no experience with taking apart my computer and i do not want to break it accidentally. I did however chance upon a topic advising him to do a CMOS reset which apparently helped that op, so i looked through the various options on the BIOS page. There was one option (f10 I think) mentioning CMOS on its fourth sub-window, so i pressed the reset option but I'm mot entirely sure if I used the right function.

I uninstalled kaspersky pure and replaced kaspersky pure for kaspersky anti-virus yesterday, dont know if this was the cause.

I am using windows 7 64 bit.

nckfrtg28 · 21 Oct 2012

On you computers Motherboard there is a round battery. Remove it and put it back in and see if that helps.

Ztruker · 21 Oct 2012

You need to run chkdsk then run Startup Repair up to 3 times.

How to run chkdsk from the Recovery Console

Boot your Vista or Windows 7 installation DVD
When you see "Press any key to boot from CD or DVD", press Enter
At the "Install Windows" screen, click on Repair your computer at lower left
At the System Recovery Options screen, make note of the drive letter assigned to your boot drive (normally C: ) and click Next
At the Chose a Recovery Tool window, click on Command Prompt. You will be sitting at X:\Sources directory
Run chkdsk
- If you did not note the drive letter of your boot disk, you can enter bcdedit and look at the osdevice line to see what it is.
- Type chkdsk c: /r and press Enter (use the letter from above).

Let it run to completion undisturbed.

If you don't have a install DVD, you can download a legal copy here:
Official Windows 7 SP1 ISO from Digital River

Make sure you get the same version you have installed: 32 or 64 bit; Home Premium, Pro or Ultimate.

See here: Startup Repair

IzalithFuror · 21 Oct 2012

I can't remember if mine is premium, pro or professional. How do i check? Can't run dxdiag here or at least I dunno how to run it from the BIOS page. Also, must it the iso be burned into a CD? Can i run it from a HDD? I don't have cds or dvds with me.

Just curious, does anyone have any idea on what is possibly causing the problem?

Ztruker · 22 Oct 2012

You can't run it from a hard drive so you need to burn it to CD or make a bootable flash drive from the downloaded .iso.

See here for an easy way to create the bootable flash drive from a downloaded WIn 7 .iso image: Universal USB Installer – Easy as 1 2 3 | USB Pen Drive Linux

Select Windows 7 from the drop down menu (at the very bottom of the list).

You will need a 4+GB flash drive.

It might be easier to just buy a couple DVD+Rs.