New rig, need your help!

Well this whole adventure has been a bit hellish, I have canceled three orders and jumped from AMD to Intel, back to AMD only to go back to Intel yet again, so I've been planning this for a week straight.

Thing is, I'm going to use the computer for music production, as well as some medium gaming (I'd like to play WAR on highest settings, as well as some other games, I'm not the type that wants to max out Crysis or whatnot). The most important thing is therefore a powerful CPU so that I can have multiple channels and software synthesizers running. Also, a Gigabyte motherboard is kind of a must, as that is the only manufacturer that I've seen uses T.I. Firewire chips, which are superb and much needed when using external audio.

So this is what I've managed to build. My budget is kind of tight, and everything is hellishly expensive in Sweden so I'll try to convert the prices to euro so you can compare more easily. My budget is about 800€ TOPS, and that's pushing it.

Antec Three Hundred: ~50€
Corsair CMPSU-550VXEU 550W: ~75€
Corsair XMS2 DHX TwinX DDR2 PC6400/800MHz CL4 2x2GB (DDR2): ~85€
Gigabyte GA-EP45-DS4 (Intel Socket 775): ~130€
Intel Core 2 Quad Q9550 2,83GHz Box (CPU (Intel Socket 775)): ~280€.
Sapphire Radeon HD4850 Dual Slot Dual-DVI 512MB (PCI-Express): ~130€

TOTAL: 750€, so I do have some headroom. I am going to buy a DVD-drive for about 25€ as well though. My question is, is the motherboard good? Which one would you recommend considering my needs? Should I get PC8500 memories? Is the PSU sufficient (550W)?

Thanks a lot for your help!

If you're going with Intel then I'd replace Gigabyte GA-EP45-DS4 (Intel Socket 775): ~130€ with http://www.gigabyte.com.tw/Product [...] uctID=2842 , which has pretty much the same specs but cheaper.

I might pick another PSU instead of the Corsair one (it's pretty solid, but I think there's better options out there like OCZ GameXstream 600w or Seasonic S12 550W).

Performance-wise, you pretty much won't feel any difference at all.

I use the SteatlhXStream 600W myself for the last year, it works fine.
It only has 3 SATA connectors though (I have 2 HDD's and 1 DVD burner), good thing my Hitachi HDD can use the old 4 pin power connector. Of course you can always buy adapters yourself, but it's up to your discretion.

If you're overclocking your system, you want RAM that actually have heatspreaders because you're going to be overclocking both the CPU and the RAM.

I'd pick brands other than Corsair (there's better ones out there for C/P and overclocking, Corsair is a solid choice).

If you can list out what RAM is available to you, that'd help as well (or link to the site you're planning to buy from).

Not much choices (I checked the site), if you're planning to overclock a decent amount.
These work better than the CL4 ones:
http://www.webhallen.com/prod.php?id=86624

Otherwise I'd jsut get the 2nd one:
http://www.webhallen.com/prod.php?id=79982

I checked out the GPU's available on the site and your 4850 is a solid choice http://www.webhallen.com/prod.php?id=88551, but if you want to save the extra $$, then the 9800GT's from the site is just as good (seems that they're out of stock though).

Yeah, the aftermarket cooler on that GPU works fine. My roommate has it and it's actually slightly shorter than the standard 4850 (a good thing).