I tried plugging the external keyboard in to different USB ports and found one that worked, so I'm able to log in and use the computer. But how do I get the laptop keyboard to work so I don't have to...

Problem: computer starts up normally and goes to the password log-in screen, but nothing happens when I try to enter the password. The computer doesn't appear to see any keystrokes.
Solutions tried:...

Thanks, damocels -- I will do that.

I went into System Restore and saw there had been a Critical Update immediately before all my troubles started. I have reset to an earlier restore point and will see what happens.

It keeps rebooting into Safe Mode. How to I exit Safe?

I removed all peripherals except keyboard, mouse, and monitor, and drained power and restarted it -- this time it restarted in Safe Mode.

Is there a way to test the power supply without ordering and awaiting delivery of a commercial tester? Given the sequence of events that led up to this failure, it just doesn't read power supply.

I can see that the NUM Lock and Caps Lock LEDs on the keyboard toggle on and off. I don't think it's a power button because the fans turn on when I power on. I've cleared the CMOS and there is no...

I located instructions for resetting CMOS (Clearing Cmos Passwords - Dell Inspiron 660 Owner's Manual [Page 104]) and have done the reset. No change in the symptoms: power light comes one, fans come...

This is what I'm looking at: http://i42.tinypic.com/2144k5i.jpg
I'm not sure where to locate the motherboard model #.

Do any of these numbers look like Models?
E145B3
MS1003
MIB75R/MH_SG MLK MB
11068-1
48.3HD01.011

I have external speakers connected -- they work fine because I've been using them with my laptop, too. How do I ID the model of motherboard? I've taken the cover off the front, but don't see any...

No beep -- all that happens is the fan comes on.

This has gone from bad to worse. It started with an error message when I went to close down, to the effect that the Start Button wasn't working and would reset on restart. I restarted; it didn't...