i want to build a silent gaming rig with i5 2500k. im not planning to oc. is there a suitable fanless heatsink for i5 2500k? the case im using would be lian li pc c32b (rack mount lian li).

thanks.

I havent seen any fanless 2500K PC, you might be able to do it at idle, but load i dont think so, specially with your current case, li pc c32b, will restrict a lot what choices you have for cpu cooler, most towers will be out, im not familar with the specs of it, but i would probably see if you can fit a Thermlaright AXP-140 or Noctua NH-C14 (crosscheck your case and components to see if you can), attach a fan that can be spin down to inaudible levels, like a Scythe Slipstream PWM, that you can lower till 250rpm and work from there to see how are your temps.

The thermalright HR-2 might be good. Someone here recently answered a similar question... but in much better detail than I am answering it.

But just adding a single 500rpm slipstream to it would add a lot of cooling capability without any noise.

Acordign to Lian Li
http://www.lian-li.com/v2/en/product/pr ... =64&g=spec
.

So most if not all 120mm fan towers are out as they tend to be 155+ mm tall. That leaves you with either 92mm fan towers or low profile coolers
Something like this would be ideal
http://www.newegg.com/Product/Product.a ... 6835186039
Maybe not the most exotic choice but it will do the trick quietly. even with a light OC.

This will not be a fanless system so why bother with passive CPU cooling? the case has 2x120mm fans having a slow speed fan (even 92mm) on the cooler will likely not make the case any louder yet keep your CPU cool.
GPU cooling and fan speeds are typically more dominant than CPU in the sound of a gamer's setup.