PSU question about new rig wannabe. Other comments welcome

[auchi]

Well hello everyone!
Im planning a new upgrade on my home rig from a Athlon x64 4200 to the new i5 just because the price/performance is making me madly wanna mount one and test it largely.

So far I've chosen this parts:

Mobo - Asus P7P55D Pro
CPU - Intel Core i5 750
GPU - Powercolor Radeon HD4890 PCS+ 1Gb GDDR5 or Radeon 4870x2 (Also waiting for the new 5k series and benchmarks)
Drives - Seagate 500Gb 7200 RPM S-ATA2 32Mb | GSkill 128Gb SSD 2.5 SATA-2 Falcon (added to external 1Tb)
RAM - Kingston PC10600 (1333) 4Gb DDR3 Dual (2x2Gb)
DVD - Asus DRW-24B1ST or anything of the sort really
PSU - NOX Urano 600W SLI
Cooler - Possibly one of these: SpinQ, CNPS9700 NT, CNPS9900 NT
Case - I had one on sight but apparently didnt bookmark it :S Was a midtower ATX with space for 120 and 140mm vents on front and back, respectively. Also some tunnel thingie on the side.

Crossfire - Yes,eventually.
OC - Yes, both gpu and cpu
Ram 1666 - I would but I'm not sure if these rams or any can go to 1666mhz without passing the 1.65v.

No links because you would see Euro prices xD


My questions

PSU is something I have the trouble working my head around. Most system go for 750w and up, ATI website recommends even higher values.
Small test about consumption gave me less than 520W for this setup, in crossfire with system load 90% and cpu oc accounted for. I'm not trying to save on the PSU or anything, it just seems to me most system are effectively getting more power than what they will need but I'm hoping I can be taught something new here

Any clues on the rams? I have been thru a few and they always say they how many hz they can reach but dont mention the voltage necessary. Apparently 1.65v is the max recommended on this board, would like to play safe.

Took me a while but found another case with the tunnel thingie, they call it a air guide. See here.
Is this any good on a case? I get the feeling it rather useless and will only take room for a proper cooler but feel free to educate me



Feel free to add any other comment

 

[obsidian86]

g skill ripjaws cas 7 is a good ram and the ocz platinium as for psu corsair 750 will suit you fine

 

[obsidian86]

http://www.tomshardware.co.uk/forum/page-270247_15_0.html

 

[auchi]

Wow thanks for the link,I had actually missed it.
Why wouldnt that 600W be enough? I have to be honest most of these famous brands for cooling and ram's seem to have largely overpriced psu's.
Even for 750W there are cheaper possibilities, what's so special about Corsair,OCZ, Antec?

 

[shortstuff_mt]

What's special about those companies is that they actually use quality components in their PSU's. There's a whole lot more to choosing a PSU than the wattage rating. In fact, the wattage rating doesn't really tell you anything since nearly all cheap PSU's over-rate their wattage specs and list the peak wattage instead of the sustained wattage. You certainly don't want to try to save a buck by going with a cheap PSU. A cheap PSU will cause all sorts of problems ranging from system instability to fried components.

 

[JohnnyLucky]

The general rule of thumb is a high quality 700 to 750 watt power supply with sufficient current (amps) on the 12 volt rail(s) can handle an overclocked system with just about any two video cards operating in dual mode.

Brands such as Corsair, PC Power & Cooling, and Seasonic have a reputation for high quality power supplies. They consistently earn high marks in technical reviews. They are stable, reliable, and come with a 5 year warranty. As shortstuff_mt already mentioned they use high quality components.

 

[auchi]

Ok guys thanks for the input