Regarding your xClio case - I have been looking at that one myself and it has recieved some excellent reviews. Just make sure you see it in person before buying - it is HUGE. That certainly has its advantages - just make sure you have the space for it.
Re gkay suggestions:
1. Definitely switch to the Corsair PSU
2. On the graphics card - I prefer the GTX 275 primarily because of the cuda feature - picking up certain processing from the CPU to speed up certain apps. Wont help in gaming but in some other apps - software designers are just starting to take advantage of it - how quickly that might accelerate is unknown tho.
Note what when you ask if it is worth the price for the performance you are asking a very subjective thing. How much power do you need? What games do you play, with what detail, at what resolution? How much more are you willing to pay to for increased performance- more than you generally do now - or to future proof?
The most partiicular issue is the i7 processor - which requires a more expensive mobo and memory. Your GTX 275 card does really not come close to utilizing the power of the i7. You could get a less expensive core 2 quad or even still less expensive AMD x4 or even X3 system and still pretty much max that card - and put the difference into another GTX 275 and really jump performance. However the Core 2 slots are on the way out and the system (mobo & memory) will not be very upgradable. The AMD option is a real alternative as its AM3 slots will have new CPUs developed for it longer.
That said - the i7 is an advantage today for CPU intensive applications like video editing and its long term upgradability is the best since you are buying the best today and it is a new socket. If I were building today - wth your budget - I would go with the i7. But if you want the best performance for the price with reasonable upgrade options - or want to use the same budget to max out gaming performance today with reasonable upgrade options, then AMD is the choice.
Finally, to answer your first question - yes it is an excellent system and will do exremely well - top end - for multitasking. For gaming it is above the mainstream range and in the lower part of the gamer enthusiast range - but depending on your requirements - as mentioned above - may more than meet your needs. But the system has everything it needs to be a MUCH faster system - all you need to do is to get a faster video card now if you need one based on YOUR gaming requirements - or add a matching one in SLI or Crossfire later if you want more power.
That article includes a link to an earlier review of more expensive boards you also might want to read for comparison. Note that his article was writtien back in March so the prices on some of those boards may have fallen. You might want to look at the standard version P6T in that article compared to the LE version in your build and the article above.
as for the case, i want it airflow to stay cool 24/7, im gonna stick with this one, also i want it big, because i heard alot of issues about big graphics cards not fitting inside the cases, so this one should be fine since its huge and cool.
as for the new monitor thanks for the new link, just a question, if u get a monitor same size but bigger resolution that makes it better? how is that?
for the new mother board, AS Rock that looks pretty good and supports SLI and not bad price ima look into that too.
and im stick with the core i7 with the gtx 275 as i been always with intel and nvidia and just wanted to upgrade.
Now to the Operating System. My suggestion would be to download Windows 7RC and then buy the full version when it comes out. You should get the 64-bit version, but if that is too much of a chore, then go with Vista Prem. 64-bit.