Need your help buddies! HD 7870 + ASUS 550w? HELP!

[PzyDuck]

Hi to all! merry christmas!

The thing is that im going to upgreade my pc. so i need some info

Actual PC specs:

Mother: ASUS M3A78 (bit old)
GPU: Nvidia 9800GTX+ plus overclocked
PSU: ASUS 550w (Real watts)
CPU: Quad core AMD Phenom II X4 810 2.60 Ghz
RAM: 4 gb
SO: Windows 8 64 bits professional
Resolution: 1920x180

Upgreade:

Mother: The same
GPU: Shappire AMD HD 7870 Dual fan OC edition 2gb
PSU: The same
CPU: The same
RAM: 8 gb
SO: The same
Resolution: 1920x1080

So, my questions are:

1) ¿ The power supply, is enough for the 7870 ?

2) ¿ Should i upgreade the CPU, or its okay ? (i dont want to, but if i have to.. i would do it)

3) ¿ You think that with this thermalthake ( http://www.thermaltakeusa.com/Product.aspx?C=1390&ID=1967 ) and 4 x 120mm coolers (don't know wich ones yet) its a good cooling setup for gameing ?

Thanks to all for the help! bye!

 

[Xttony]

1. You don't need to upgrade your PSU now but consider that in your next updrade.

2. You don't need to.

3. That is a fine case but I don't think you need that sort of cooling with 3 fans.

 

[Commandermadi]

1. Its just enough for it.
2. I guess you should upgrade it, in order not to bottleneck your GPU performance.
3- The case is cool.

 

[PzyDuck]

Best answer selected by PzyDuck.