Current COOLING and PSU enough for my new Build?

Hi all and first of all thank you for your advices.

I am planning to upgrade my Desktop PC the next week.
Right now I have:
Motherboard: ASUS P5WDH DELUXE (Socket 775)
RAM: 4GB DDR2 800Mhz
Processor: Intel Quad Core Q9550 2.83Ghz
GPU: Nvidia QUADRO FX 3800
HDD: Seagate Barracuda 7200 320 Gb + 1.5 Tb between a copule of portable HDDs one of them 1Tb with USb 3.0
Power Supply: Thermaltake Thougpower XT 775 W
OS: Windows 7

Ok so I just want to upgrade The motherboard, the RAM and the processor, keeping the rest.
The main use will be gaming as best as posible and 3D Editing with 3DsMax, Zbrush and Photoshop mainly.

I´ve been doing a lot of research And I am finally going to buy the following:
- CPU: Intel Core i5-3570K
- MOBO: Asus P8Z77-V PRO
- RAM: G.Skill Ripjaws X DDR3 1600 PC3-12800 16GB 2x8GB CL9
- (Just for let you know I have another QUADRO FX 3800 waiting for a motherboard with SLI compatibility (my current mobo has not). That would make a couple of QUADRO FX 3800 working on SLI in the new build.

The only thing that still worries me right now is the cooling and my PSU.
- Will my Thermaltake Thougpower XT 775 W be able to handle all this plus the double Quadro in SLI?
- If I am planning on overclocking, will the default intel cpu cooler plus my 4 case fans be enough? If not what are your recomendations?
NOTE: This is my current case: http://www.apevia.com/ProductsInfo [...] CRUISER-AL

That PSU should be fine, yep. With the stock intel cooler, you can overclock a bit. How much depends on the voltage and clockspeeds. I would say somewhere around 4-4.3GHz is possible on the stock cooler.

Thank you very much! To say the truth I know nothing about OC, I am planning to learn some with the new PC.
So I should have no problem with the current case cooling and the default intel cooler! That´s great!
Thanks again