Hello all! i have decided that i am going to build myself a gaming pc soon! i have a budget of around £600 for the job and have decided i would like a cooler master 430 case as they seem to be cheap and effective but i would really appreciate it if somone could peice me together a rig from the best going rates they know!
i want it for games such as guild wars but i really would like the absolute best bang for buck that there is right now
While I appreciate all the constructive criticism you've been able to provide in this thread (note: sarcasm), that's not true when you apply boundaries or restrictions (in this case, OP's budget of £600). Even if we take away that budget, though, it can be better for virtually the same cost (see Lighter's post just now).
I'm not sure - my school used to offer retail copies of W7 Ultimate for $20 last year, but now they only offer free upgrade discs. The only other cheap alternatives that I know of (that I'm willing to suggest) are getting an OEM or "system builder" copy, or get Linux (many games can run through Wine, but it's never a guarantee)
You may be able to get it through Dreamspark; or, if not, perhaps another Windows OS for the time being.
XP wouldn't really hinder your hardware in any way - 64-bit Windows XP (Service Pack 2) and 32-bt XP (Service Pack 3) still have official Microsoft support until 2014, so a lot of people are still using it, and games still run very well on it.
Depends on what edition of XP you get - if you can get 64-bit non-Starter edition, you'll have a RAM limit of 128GB; otherwise, yes, you'll be limited to 4GB. And that's up to you whether or not having DX11 would be a waste - not every new game uses it (many still use DX9, and offer DX11, though some games only make use of DX10/11), but also keep in mind that installing XP on your system isn't going to lock you into that forever and eternity, you can upgrade whenever you get Windows 7 or 8 (if that's the direction you want to go).
That looks to be what you want, but it also appears sold out. I don't think it'll be easy to find XP available in retail. I'm looking as well, but I'm not familiar with sites that'll ship to the UK, so I can't promise I'll be of any help.
Alternatively, you do have the option to cut back on some of the hardware and get Windows 7 - since you're not planning on overclocking, an i3-3220 would be more affordable option (£92~96) and wouldn't compromise your performance too much (remember, games are more dependent on the video card). This would also let you get a lower wattage PSU, as 650W for an i3/7850 system is pretty overkill - a good 450 or 500W would do just fine (and still have room to expand).