ThermalTake 680W PSU

[gidyn]

I am looking for a PSU for a new computer. My current options are ThermalTake W0057 and W0049. Tom's review of the X0057 found fault with the power meter, so this isn't really a reason to choose it. Looking at the specs (see http://www.thermaltake.com/purepower/w005758twv500/w005758twv500.htm and http://www.thermaltake.com/purepower/w049atx12v/w0049atx12v.htm), W0049 has lower output across the +12v rails, but there is a third +12v rail and more power on the +5v. What are the different rails used for (pardon my ignorance)?

 

[mozzartusm]

Ive got a TT680 on a 3.73EE CPU that usually is running between 4.6Ghz and 5 Ghz. RAID 0 and 6 other HD's 2 DVD Burners and it does just fine.

ASUS P5WD2 Premium
Intel 3.73 EE @ 5.6Ghz
XMS2 DDR2 @ 1180Mhz

<A HREF="http://valid.x86-secret.com/records.php?PHPSESSID=792e8f49d5d9b8a4d1ad6f40ca029756" target="_new">#2 CPUZ</A>
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