Which PSU should I get?

[FATAL FLAW]

you think 610 watt wont be enough?

 

[freestyler105]

Those two aren't even in remotely the same category...but stay far away from the Raidmax. The PCP&C one is probably a good choice, it'll be more than enough, it could even power two of them in Crossfire:

ATI Radeon HD 4870 System Requirements

* PCI Express® based PC is required with one X16 lane graphics slot available on the motherboard
* 500 Watt or greater power supply with two 75W 6-pin PCI Express® power connectors recommended (600 Watt and four 6-pin connectors for ATI CrossFireX™ technology in dual mode)

 

[FATAL FLAW]

will this PSU be good for the 4870?

 

[freestyler105]

Yes. Get this one:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703005