This technique works on: Windows XP (only one I've tested it on.)

This technique is for: Computers which have an ide cable with only one drive on it.

When XP boots it automatically searches all your ide cables for new hard drives. If you know that you've only got one, the computer will waste boot time looking for more. To correct this:

Right-click on 'My Computer' and click 'properties'.
Under the 'Hardware' tab choose 'Device Manager'.
Click the + sign next to 'IDE ATA/ATAPI controllers' to view all of them.
Choose either the primary or secondary IDE channel, by right-clicking and choosing properties.
Choose the advanced settings tab.
Of Device 0 and Device 1, the one with a drive connected will be greyed out, so you cannot mess up your computer. On the other one (the one not greyed out) change device type from 'auto detect' to 'none'.

Press ok, repeat the process for the other cable if necessary, and close the device manager.
Your computer will now no longer waste time during loading looking for additional drives.
This trick has improved the boot time on every system I've tried it on, in some cases by up to 30 seconds.

Please note, whilst I looked through all the tips here, I cannot be absolutely sure this tip hasn't been given before.

Thank you. I`ve tried many times to speed up XP, read a lot of stuff and every attempt failed. It`s exellent trick for the purpose.

Very good indeed!!

Welcome to Daniweb my friend :)