how much ram?

also, can i have (for xp32) 2gigs of dual channel instead of 14 gigs of single channel, can this be done? because i know that my os only supports 3-4 gigs of ram.

I'm not sure I understand your question about 14 gb of single channel RAM, but I'll try to give you an answer

XP 32 only "sees" between 3-4 GB of RAM - it's the way 32 bit OSs work, as well as the fact that some of the hardware reserves some of that memory for itself (GPU, etc)

How much RAM should you get - I would say try to get a 2x2GB kit of DDR2 800 low latency RAM (4-4-4-12, 5-4-4-15, etc) that has close to standard voltage (1.8v).

Hope that helps you out a bit. You ought to be able to find the RAM for around $50 US, so that's less than what I think you are willing to pay in pounds.

I would just get a matching pair of 1 or 2 gig sticks. If you have a board with 4 memory slots and use them all, be sure to enable memory mapping in the bios. I like crucial or corsair, but my compaq pc came with samsung, which also works well. With 32 bit vista, I noticed little difference in performance going from 2 gigs to 4 gigs of ddr2. And there's no difference in dual channel memory versus 2 identical sticks; it's mostly a marketing ploy. Dual channel mode is determined by your motherboard chipset and color coded slots. Just use the same color slots, and if your board is dual channel capable, it will work.

sorry bout the random no, i meant 4 gigs, and if xp will then recognise it as 2gigs f ram or is it it too much for it?, also which is better 2 gigs of dual channel or 4 gigs of single channel

what about 2 gigs of this?
http://www.amazon.co.uk/OCZ-PC2-6400-240-Pin-800MHz-4-5...

Your better off checking newegg.com, better prices, availability, variety, etc.

Try this RAM for £40. 2x2GB

Corsair 4GB Kit (2x2GB) DDR2 800MHz/PC2-6400 XMS2

^Good stuff. Here are a couple more options:
4GB OCZ 800MHz for £44.95.
http://www.amazon.co.uk/4096MB-DDR2RAM-PC800-Gold-CL5-5...
4GB Corsair 800MHz for £42.68.
http://www.amazon.co.uk/Corsair-TWIN2X4096-6400C5-PC2-6...

With a setup like this you get 4GB of dual-channel RAM, plus the room to upgrade to 8GB in the future (if you ever get a 64bit OS.)

A 32 bit OS with see/use a total of 4GB of memory. Theory being what it is, you should see a bit better performance with four, one GB sticks than two, two GB. Go get 'em...

A 32 bit OS will address 4 gig of memory total.
What you have to bear in mind..... that includes ALL the memory in you system.
Video cards, harddrives, CPU cache memory, etc. These are all assigned memory space first, and after that what is left over is available for you to use in main memory, or RAM.

This is something to also bear in mind if you are thinking about getting a 1 gig video card......boom there goes 1 gig of main memory right off the bat.
If you plan on doing that, I would suggest you bite the bullet and pick up a 64bit OS.

Just get 4 gig. 2x2 for 4 gig is cheap enough these days.
Also, I don't know why someone suggested 4X1 sticks is better, it is not.
Get 2x2....if your motherobard supports 2 gig sticks, check your manual. You ususally have less problems running only 2 sticks.

The extra memory that is unused does not harm anything, and you will be assured that Windows is using all the memory that it can.

2 g of dual is always preferred because of timing with the mobo,you can install 2x2 g windoze will work quite well ,,just will not see all the ram,remember windoze is just a GUI slapped on top of DOS with all it's limitations and lack of security...