Overclocking help and CPU cooling

[xpygmy]

I am planning on overclocking i5 3750k to 4.0 ghz and was wondering wether I need a new CPU cooler because I want to make sure the CPU is as cool as possible do I can get the best out of the CPU. Also want is the max I can overclockers it to with a Cooler master silent pro modular (500w) psu and a Gigabyte Z77-D3H Intel Z77 motherboard. Also what software do I need to overclockers it and to make sure it is stable and so on.
*And final question, I am going to get this radeon 7870 http://www.overclockers.co.uk/showproduct.php?prodid=GX-010-VX&groupid=701&catid=56&subcat=411 *and was wondering whether it should be overclockers and again what software should I use, how do I do it and do I need another programme to make sure it stays stable and cool and so on.

Sorry that I am a overclocking newb.

 

[leoncao]

After market coolers are cooler and quieter than your stock one. If you want to overclock, you should be getting one. Lots of choices out there, really down to your budget. I use an Arctic freezer 13 (~£25?). It baby sits my 2500k @4.4Ghz under 70c running prime95. You actually need no software to OC your CPU. I believe it is quite obvious in UEFI bois nowaday. Check your bois at advanced setting (or similar) you should be able to set the clock speed of your CPU quite easily. All you need to do is change the multiplier to, say x40, if you want 4Ghz. Then run prime95 for a few hours and check the temps and stability.

As for your 7870, you can use MSI afterburner or whatever software the manufacturer supply (e.g. asus gpu tweak, sapphire TriXX Tweak Utility etc.) or even AMD CCC overdrive which comes with CCC package. Check reviews see how much OC potential your particular card might have. Good luck