Overclocking power draw

[AnUnusedUsername]

I'm considering buying a 2x120mm closed-loop cooler for my CPU (along with a new case that I'm buying regardless) to replace the low-profile cooler I'm stuck with right now due to form factor.

But I'm not sure that my PSU could actually handle any notable overclock on my CPU.

My system:
i5-2500k
R9 290
8GB RAM (DDR3@1333)
ASRock P67 Extreme4 Gen3 mobo
SeaSonic x650 PSU (650W, 54A on +12V)
128GB SSD and 500GB HDD
CPU cooler is currently a Noctua NH-L12

From what I can find, my GPU will peak at ~300W draw, and my CPU at stock clocks around ~100W. That at least in theory leaves plenty of headroom, but then again, ATI recommends 750W for the R9 290 alone, so, I'm not sure what to think.

So, thoughts on whether this is a good idea, or should I just stick with my current cooler and a mild overclock (assuming the better airflow of a full tower case allows for it)? I know the 2500k typically has a lot of headroom, even 4GHz should be a decent improvement over stock.

For reference, the case I plan on buying (assuming it's back in stock by black friday) is a Lian-Li v1000LWX. If not, I'll find something else with 3 120mm fans in the front, no door or panel blocking said fans, 2 120mm on top, a side window, and no plastic (apparently that's a hard combo to come by).

 

[Mr5oh]

Every time I've measured power consumption before and after over clocking its always roughly 10-15% increase. So overall over clocking doesn't make a huge difference, power consumption wise.

 

[rubix_1011]

My sig line has a spreadsheet that helps you determine CPU overclocked TDP as well as 85% efficiency from power draw to heat expelled. It also allows you to choose a watercooling loop based on the required radiators you'd need to effectively cool your components.