Dell d800 latitude performance very slow

SOURCE: Dell Latitude D800 Processor slows down

This is the SpeedStep technology feature of your processor. It will speed back up to 1.7 GHz when it is needed. Slowing down the processor saves battery life.

SOURCE: Dell Latitude D800

This may be SpeedStep slowing the processor to save battery life. It speeds up when it is needed.

SOURCE: Dell Latitude D800 Boot Problem

Did the diagnostics pass the RAM and the hard drive.
You should check the BIOS settings to see if the hard disk is detected, if possible reset the BIOS back to the default settings and see if the computer boots up.
If not :-
Then it appears that the operating system is either corrupted or system files were deleted or infected with viruses.
Your only option is to do a operating system repair or a complete new install of Windows.
I recommend you do a new install.

SOURCE: Slow speed, fan coming on loudly in Dell D800

Yeah the slowdown is the laptop throttling back due to overheating.

When you do processor-intensive work like - streaming videos - the laptop overheats. The fans come on loudly.

When the computer heats up despite the fans, the processor throttles back to relieve the heat.

When you reboot your machine, it stops performing intensive work, giving it a chance to cool down. It's not restarting that fixed the problem it's the fact that the laptop cooled down.


So here's what you do. Get an air duster and blow all the dust and gunk out from your fans. They are most likely clogged with dust and that's what's causing your cooling problems. If there are large dustballs in there, use a tweezers and pull them out. Get as much out as possible.

SOURCE: bios password dell d800

Remove BIOS battery. Short BIOS jumper or leave the battery out for a long time(Over night,maybe) This should default the BIOS to having no pass word present.  If that doesn't work then evidently Dell has one within the BIOS . Just ask them.