i have to agree with Cobra on this. make your cash work harder. it'll save you money in the future.
this is what i would buy with your cash:
AMD Phenom II X2 Dual Core 555 3.20GHz Black Edition £85.76it has twice the onboard cache (this is important these days) and is built on much better technology.
Asus M4A78L-M LE AMD 760G (Soc ... roATX Motherboard £46.99 but if you research, you should be able to find a motherboard that lets you unlock the two locked cores on the Ph555 (quad core chip for £85 anyone?). as the chip i posted is socket AM3, you need to have at least a socket AM2+ board to use it. it also means you can drop a socket AM3 quad core or even a hex core with only a small bios update. this will help you future proof your system a bit.
Patriot Signature 2GB DDR2 6400C5 (800MHz) £29.36
Point Of View GeForce 9800 GT Green Edition 512MB £72.84 green edition = slightly underclocked to save power. i try to stay away from those but you're running a tight budget.
in terms of age, the 8800 is now 4 generations old (8xxx, 9xxx, 2xx and now 4xx). it was released in the USA in December 2007. at least with a 9800, you'll be one generation closer to the high end of the market.
total: £246.12 delivered.
to be honest, if you had £325 rather than £225, then you could do alot more. maybe the best thing for you to do at this time would be to hold onto your money and save £100. it means you could squeeze the graphics card a bit more and maybe get some more ram.
there's nothing worse than building your own machine and then think that you should of held off so you could go bigger. something like this:
VTX ATI Radeon HD 5770 1024MB GDDR5 £123.36 and i can garentee it will increase your overall gaming pleasure.
if you're going to buy the 8800GTS, buy a 2nd hand one and fit it with an after market heatsync and fan. i might know a guy who is on the verge of upgrading his system and he currently has a 8800GTS or GTX. i think he might end up selling it.
do not buy that ram you posted. it's over priced and you'll regret it.
the athlon is a good chip but as Cobra said again, go Phenom. you'll get so much more bang for your buck. the motherboard (imo) is a step backwards. and if you ever wanted to upgrade again in the future, i can bet you'll need a new motherboard to meet the requirements of the upgrade.
those parts i have posted are very similar to the system i have. i used to be able to run most games at a medium quallity level and still get good fps. i have since upgraded the graphics card (GTX470)and now i don't own any games that my system can't run on full settings. so i can say you'd be more than happy with the results of the system i have posted.
EDIT: i'm not an ATI guy but you might be able t oget more GPU for your money by switching to ATI. i think Cobra knows more about ATI than i do so i couldn't recommend an ATI product unless it's the higher end cards (as i have compared them to Nvidia cards).
EDIT 2: you'll also need a cooling solution for the new hardware. that system will run alot hotter than your old one.