For now its a Evo Labs ATX Switching 500watt PSU but I'm aware that it will need to be dramatically increased when i get a graphics card in 2-3 weeks time and additional small solid state drive dedicated to the OS in which Vista is what I've installed 3 hours ago!.
Thanks for the reply clutchc and what would you recommend to make the most of the hardware ive presantly got?.
I can't seem to find much in the way of specs on that PSU. So I will assume the worst and suggest you opt for a discrete card that doesn't need a PCIe power cable; i.e. one that gets all its power from the slot itself.
The most capable card today in that class is the HD 7750. It is the successor to the HD 6750 which needed a separate power cable. The 7750 does not, but has the same graphics capability. If gaming is your main interest, it will provide good frame rates in today's games at resolutions up to around 1680x1050. Higher, if you don't mind backing off on the settings quite a bit.
If you are in the UK, you won't be able to use the above link. But perhaps someplace like Ebuyer.com or Scan.co.com will have the same items. Your unlocked 3GHZ Athlon II quad core should be able to keep up nicely with that card. If you have 64 bit Win7, you may want to increase your memory to 8GB. If not, 4GB will still be fine for gaming.
As with clutch, I agree that the PSU you have is basically an unknown. However, I would be inclined to up the usable graphics card to the Radeon HD 7770. The difference in power consumption is about 43w vs 78w which I believe even a crappy 500w can run without dying.
I do recommend that you save up money for a new PSU though that is of good quality. I recommend Seasonic, Corsair, XFX, Enermax, PC Power & Cooling, OCZ, and Antec. Not an immediate purchase, but something to put on the radar for 2013.
Yes, I admit I was being a bit conservative with my gfx card recommendation.
But I was basing it on the fact that what little I could find on the PSU seemed to indicate it didn't even have a single PCIe power cable. Usually a dead give-away that it wasn't intended for powering a discrete card. But in all likelihood, you are probably correct that it could handle the HD 7770.