OK, have recently purchased an athlon xp 2800+ on eBay, but it appears in windows only as a 1500+, and whats worse is it only operates at 1.4 GHz. my motherboard is a MS-7021(KT6V-LSR). i would try overclocking but i am a bit amateurish, especially on older boards.
can anybody help me?

Clear cmos, load bios default, if no luck. Look into any bios update for that mobo.

It is a socket A mobo ... handles up to the 3200+ Barton CPU.

The 2800+ came in a couple of flavours too ... the 2250 T-Bred was the fastest XP in terms of silicon they produced for that line ... it was a hot little mother to try and cool ... the Barton 2800+ ran a little slower but had twice the cache.

The 2800+ in either flavout was about as fast as a 2.4 Northwood ... by my rating system ... and the Northy could OC a bit faster too ... up to 3.2 easy for the 533FSB model which was populat like the XP1700+ and 2500+ Bartons for overclocking.

http://www.lostcircuits.com/cpu/amd_xp2800+

But ... there are a couple the T-Bred here:

http://www.cpu-world.com/CPUs/K7/A [...] DKV3D.html

Frequency (MHz) ? 2800 (rated)
2250 (real)
Bus speed (MHz) ? 333
Clock multiplier ? 13.5

or the Barton here:

http://www.cpu-world.com/CPUs/K7/A [...] DKV4D.html

Frequency (MHz) ? 2800 (rated)
2083 (real)
Bus speed (MHz) ? 333
Clock multiplier ? 12.5

Remove, clean, regrease and reseat the cpu - clean the base of the HSF before regreasign that too.

Fire it up and hit del to get into the bios and check the max multiplier ...

And check the size of the cache in the boot screen - the Barton has 512 ... the T-Bred 256.

That will help you set the multi and fsb.

Hope this helps.

Let us know how you go.

thankyou! works a treat now!
looking at the receipt of the computer now, originally it came with a 2400+ which was underclocked to 900MHz for some reason.
now hopefully i will be able to get a decent game out of my graphics card.