Toshiba satellite laptop model 5105-S501

If you purchase a new OS disc of your choice, assuming it will work on your laptop, just palace the disc in the drive, boot from the disc and follow the on screen prompts.
Hope that helps.

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Tear it down to the bios battery and remove then replace it. This will reset the bios to factory and wipe all preboot passwords out.

Go to "Microsoft Updates", if the Drivers are missing or need updating Microsoft will identify it, and updates should be available for installing.

Look under the hard drive for a this 'mercury' battery

ruhh row...The only option I know of is to remove the cmos battery for about an hour. toshiba support may have a "generic password" that can be used.

When you just switch on the computer look out for the first screen(before windows even starts up).and try to quickly read usually it will tell you what button to press.depending on the make its usually f12 or del but first check what your model says.

I found a service manual here for your laptop:

http://www.csd.toshiba.com/cgi-bin/tais/su/su_sc_docTOC.jsp?moid=191877&rpn=PS511U&ct=UG&soid=210682&BV_SessionID=@@@@1298652900.1218912241@@@@&BV_EngineID=ccccadeelljifekcgfkceghdgngdgmm.0

Not sure if this will help you or not.

Note you will need adobe acrobat to read this.

There is no BIOS setup on that (or most for matter) Toshiba laptop. If you need to tell it what drive to boot from hit the F12 key when you see the Toshiba Logo then use the left and right arrow keys to pick what device you want.

Yes it could be, the notorius GeForce2Go is a replaceable card on that model. I have seen, lines, blurry text, and Boot loop issue caused by it. Be warned, the replacement card is expensive.

Cheaper & better finding a complete laptop with busted screen.
and removing the card only. Then you will also have other spare parts.