I have a quiet configuration (two Scythe Slipstream@400rpm for the case, an SSD instead of an HDD) and are looking for a CPU heatsink that's also inaudible. The case constaints it to about 130mm height (in a HTPC case) and enough clearance for the non-low-profile Corsair memory. CPU is an Intel 2500K (standard-clocked), GPU is integrated.

The ones I found are:

* Coolermaster Gemini II SF524 (with another fan?)
* Noctua NH-U9B (no pwm fans?)
* Prolimatech Samuel 17 (with a quiet fan, e.g. Scythe)
* Scythe Samurai ZZ

Are there any others to consider? Which one is best?

Hi, i bought the Coolermaster Gemini II SF524 last week and got to say i am pleased with the resuilts so far, i have a phenom x965be and it cooled it down with the 120mm fan real nice and have not used the fan adapter thst came with it and just plugged it in with the 3 pin plug and my motherboard automaticly runs the volts for me and at full load and a temp of 36c the fan is running at just over 1100 rpm and is not to loud at all and at normal load watching media center it has bin down to as low as 600rpm and a temp off 22c

If you are going top down, you want to leave one fan width of space at the top unless you are using one of the new under-slung fan designs. But even there you would still want perhaps 10 or 12mm of breathing room for the fan.

I recollect that the NH-U9B is 135mm so you should double check the clearances. I don't believe the Samurai ZZ will fit if you want to provide sufficient breathing room to the fan.

Take a look at the Noctua NH-C14 with just one fan... or the Noctua NH-L12 with both fans. The Samuel 17 is a nice cooler, but if either of these Noctua's fit in, they are likely to provide more cooling capacity. The Samuel 17 probably has enough cooling capacity for a 2500K but the Noctuas will have more. And depending on the ventilation of your case, and the ambient temps you operate it in, maybe the extra capacity is worth it.

There is something to be said for the Noctua NH-L12 with two fans. You will never have a catastrophic failure if one fan goes bad without you noticing it.

I checked the NH-U9B again; it's 125mm high.

SilverStone Nitrogon NT06-E 82mm without fan so in 130mm you plenty of room for the heatsink and fan and breathing space above the fan. With 5 heatpipes should be ample for 2500k (as long as not overclocking much) and not very expensive either, unlike the huge NH-C14. Not sure about memory clearance.
Seb

According to SPCR testing the Silverstone is not a good performer. It may be OK if nothing else fits, but I think even the small Kozuti outperforms it.
http://www.silentpcreview.com/article976-page1.html

I got the Samurai ZZ yesterday and can confirm that it is only 95mm tall with the 92x25mm fan fitted.

Very happy with the performance so far without the fan fitted (I have a 220mm side fan). Hope this information helps.

Thanks for measuring it, kiblams! Sometimes it's hard to know which number is supposed to be the height.

I'm somewhat turned off by Noctua, since I'd have to pay for expensive fans that I won't use (I only need one fan since the case fan is right next to it and I would like to have a lower RPM PWM-fan).

Anyway, I guess it comes down to the Samurai ZZ, the Noctua NH-U9B or another Noctua.