Which PSU?

This is urgent!! please!??

Neither are good. Never heard of Casecom and Thermaltake PSUs are highly hit and miss.
Neither are even the basic 80Plus standard which might not seem important but it usually means they are pretty shoddily put together using inferior components, even entry level PSUs from quality OEMs will generally meet 80Plus or 80Plus Bronze. The Casecom has no warranty info and the Thermaltake only has 2 years (very poor)

There isn't enough provided information to give you much more info, but I'd advise a rethink.

Both are not great , I would not use either of them , but it's your money , of the 2 thermaltake , but really not great and at that price would avoid . I paid 20.00 less for my Antec HCG 620M .
I'd suggest looking at Corsair , seasonic , Antec or even PC Power , you can find a good real 500+ watt psu on sale for those prices

How about this thermaltake , 5 year warrranty 80+ bronze $1.00 more
http://www.stardot.com.au/thermaltake-500w-tr2-bronze-p...

read about cheap powersupplies and ratings
http://www.jonnyguru.com/modules.php?name=NDReviews&op=...

more thermaltake read on , thermaltake is all over the place , some are really good , and many are overrated crap
bad
http://www.hardwaresecrets.com/article/Thermaltake-Pure...

good , but drawbacks , like limited connections .
http://www.hardwaresecrets.com/article/Thermaltake-Lite...