£300 upgrade build

You should get 4GB of DDR2 800 with a 1.8V requirement. That's the most important thing.

Crucial overvolts their RAM to get those lower timings... they (Crucial sticks) quite often won't boot up due to the voltage reqs. They really don't have a good rep any more.

This Corsair set will do:
http://www.ebuyer.com/product/130429

If you need to, grab a 4670 instead... or get this 9600GT:
http://www.ebuyer.com/product/147945

A P43 board would also cut your cost down:
http://www.ebuyer.com/product/149274

Thanks for the tip on the memory,
Just a Question though. is it really worth it to get 4gb? im going to be using a 32bit os (XP) which means im only going to be able to access some of that (2.75gb i think) so for the price difference wouldn't it be better to get 2gb instead (2x1gb)?
as for the mobo also thank you! it looks great and the reviews say its good, just one question though is there and disadvantages about the P43 chip-set (think I read some somewhere ??) over the P45
Thanks again

RAM is cheap, and you will have the option 2 move 2 64 bit OS. BTW, why xp? Vista 64 works much better with the new hardware, and windows 7 coming soon.

The only actual differences in the chipset are:

1) Ability to crossfire. I felt you likely weren't planning to crossfire.

2) Ability to use DDR3. Only some P45 boards use DDR3, but the chipset is capable of it.

Now, beyond the two differences in the chipset, there can be differences in the way the boards are laid out. A P43 board may have some cost-cutting going on... perhaps limiting it's ability to overclock or missing some features included with P45 boards from the same manufacturer.

A P43 board from ASUS or Gigabyte is going to be adequate for a tight budget however.

The amount of memory available under XP 32 bit is going to vary according to a number of factors... I always want to launch into an explanation here but I'll avoid it this morning.

Looking over your hardware I would guess you'll have over 3GB available.

I think DDR2 is near its bottom price. I suspect your next system will still need it, and so it's a good investment. Tests show that the more memory you have, your MINIMUM FPS tends to come up in games, thus reducing those times when the game struggles.

Finally, P45/P43 boards don't seem to like having all 4 memory slots occupied. Takes extra tweaking usually. A 2X2 kit up front will avoid that.

If you check around, you'll find just about everyone in the know is running Vista 64-bit now. I myself own both XP 32-bit and Vista 64-bit, and I removed XP from my system. Vista 64 is more stable and actually faster on my system, and every game I play works fine on it.

Thanks for the information, Didn't know about the 4 slot thing so yeah 2x"2GB makes more sense then 2x1GB even if just for future proofing. As for the OS, I was going to get Vista but at the moment I cant justify it with it costing £65 and up and with Windows 7 on the way i think ill just hold out on XP till that arrives then look at the prices (having been brought up on pre-built systems i always feel cheated for some reason when i have to buy an OS  )

Just out of interest when I upgrade my pc would there be any problem just loading up my current iteration of windows (aka not doing a complete reinstall) as my HDD blew over Xmas and I've only just got windows working the way I like.

If so should I uninstall as many drivers as possible on the final boot up of the current hardware system to prevent as many problems with the new hardware as possible

XP probably wont run, you can use software like UIU

You can try to do an "XP repair installation" (Google it) but you should plan to do a fresh install.

Use the "files and settings transfer wizard" (I'm a bit dim on the exact name atm, past my bedtime) to save all that XP information you like to the next installation.