Dell latitude 2120 won't boot up and cap lock keeps blinking

SOURCE: dell latitude d610

try changing your keyboard it might be shutting down because of a keyboard error and it seems like your caps lock is acting up a bit i would suggest to try cleaning it first and seeing what you could do about that. If you can log into bios possibly you might be able to turn of the keyboard error check hope this helps

SOURCE: Dell Latitude D600

It is the Hard drive on the system. Hard Drive is failing. Another Error code for the Hard Drive is Error Code 7. Check BIOS setup if the system still detects the Hard Drive as well. You may want to consider changing the Hard Drive on the system.

SOURCE: caps lock key broke off

You'll need a new keyboard.

SOURCE: Dell Latitude D610 won't start. Caps Lock flashes a few times.

Hi,
http://support.dell.com/support/topics/global.aspx/support/dsn/en/tree?c=us&cs=28&l=en&s=dfb&journalid=656DBBED5AFCEABBE040AE0AB8E17A47&treeid=084A4C3E0A9C9EEEE0401E0A55172321&Query=bm8rcG9zdA==&SystemID=LAT_PNT_PM_D610&ServiceTag=&contenttype=-1&os=-1&component=-1&lang=-1&doclang=en&toggle=true&dl=

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SOURCE: Dell D410 Latitude won't boot up when connectd to docking station

That blinking cursor is the way in which the BIOS is telling you that Windows is missing - its most critical, core files have been corrupted beyond repair. The only thing you can do is to reinstall using the recovery cd or your own Windows install disk.