Alpenföhn is steadily working on establishing as a reknown cooling company. Their Peter VGA cooler we tested before was a high end solution. The K2 two tower CPU cooler aka Mount Doom, seems to target the same enthousiast users.

 

   

 

Very solid and neat packaging. All the specifications are clearly listed on the side. This cooler is compatible with all Intel sockets S775/1156/1155 and even S2011 after requesting the free mount upgrade. All AMD options are covered too AM2/AM2+ /AM3/AM3+ and FM1 socket:

 

   

 

 

 

You can clearly see now, why we always refer to it as a twin tower design. A total of 3 fans can be mounted, though there are onyl two included in the box. A 120 and 140mm fan of the WingBoost type.

 

  

 

The trapezoidal design of the fins is baptized as MnTal ( Emmental surely rings a bell here) : Minimised noise Transfer at Low Airflow technology. It should allow for a more optimised airflow over the soldered fins, to enhance the cooling performance. Sounds real good to me. Does it work, that's another thing.

A total of 8 6mm U - shaped heatpipes are being used, to conduct the heat from the nickel plated copper base plate to the massive fin area. Similar as to the fins, the heatpipes are also soldered to the baseplate:

 

   

 

The full copperbase is extremely flat and the nickel plating has an impeccable finish. The topside of the bottomplate has got several heatisnks for extra heat dissipation and a big cutout for the mounting plate.

 

    

 

 

 

The multi-socket compatible backplate is a joy to work with. Just insert the screws, slide over the rubber protective cover and push the pins through the motherboard socket openings.

 

 

 

 

 

 

 

Then use the appropriate black plastic washer and secure the bracket with two nuts. Put some thermal paste on the CPU, position the cooler and secure the top plate by tightning steadily the two spring/screws. If you have tightened everything you will have a rock solid mount and the cooler is firmly held in position.

  

 

 

  

 

  

 

 

 

For our test bed we opted to just include our hottest CPU : the i7 970 ES Gulftown from Intel

• Asus Rampage 3 Extreme
• 6Gb Corsair Dominator ram PC12800C8 (with two removed top heatspreaders )
• MSI GTX480 Lightning card

We overclock the i7 970 CPU to 4.2Ghz via 200 Bclock and a 21 CPU Multiplier. The Vcore used is 1.42Vcore with 100% Loadline selected.

The CPU was allowed to Idle for 30 minutes in windows, temp monitoring performed by Real Temp program. The average off all cores is being calculated and used in the graph. For the loading test we allowed the Prime95 program to run an hour at custom set of 12 - 12K.

 

 

 

 

Other coolers used in this review ->

 

Liquid All in One cooling solutions :

 

Coolit :

• Vantage and Eco model

 

Corsair :

• Hydro 50
• Hydro 60
• Hydro 70
• Hydro 80
• Hydro 100

Air Cooler :

 

Alpenföhn

• K2 with boxed WingBoost fans

Thermalright

• VenomousX with Push and Pull setup  : 1100 and 2000rpm fans

 

Too show you how tight the ram fit is we installed the low profile GSkill Sniper kit, only a few mms to spare...

 

 

 

 

So here are the results fo the belgian jury. Keep in mind that this i7 970 ES CPU is a natural hothead. Even with just 1.4Vcore it can bring some older cooling devices onto their knees. A solid Phase change unit has got heaps of trouble to keep it benchstable at just 4.6Ghz. Not even talking about priming it, like we did in the chart below.

 

 

When we hooked the K2 to the CPU fan connector and allowed the PWM mode to control the fans we obtained similar performance as our humble Thermalright VenomousX cooler. The latter being equipped with two 1100rpm fans. Once we disabled the PWM fan mode and allowed the two Boost fans to spin freely we got a nice extra 6°C temp drop. Allowing the K2 to settle itself in the middle of the pack. Keep in mind that all of these all in one units, ( besides the dual rad H100 )  are allowed to suck in ambient air from the room. This makes them optimally perform, but also makes them dump all of the heat into the case. Reversing the air flow of the liquid units fans results in a lower case ambient temperature. Setback is that the CPU temps rise 2-3°C in average under load. If you are still following my reasoning, this would make the K2 cooler to settle itself on the top part of the above chart. Just behind Corsairs Hydro100 unit. Adding a 3d fan yielded even beter performance. We in fact replaced the 120mm WingBoost fan with an Antec 2000rpm fan, plus added a similar one on the other side. Though the two used 2000rpm fans are very audible and the noise level went up drastically. The small gain we got at the cost of the noise doesn't make it all worthwhile. Conclusion : The two boxed fans are more than adequate !

Alpenföhn's K2 CPU cooler is one of them big tower air coolers that will make you turn your head when you spot them. It's not alone by it's size that it manages to impress. It's overal design from the 8 massive heatpipes, the secure robust mounting system, to the trapezoidal pyramid like shaped fins. Included are two versions (12cm and 14cm) of the Wingboost fan series in white black theme. If you had to buy an air cooler, just for the looks of it, then it's hard to overlook Alpenföhns K2 masterpiece.

 

 

Performance wise it's a solid air cooler. Though comparing the sheer size of this beast, it leaves me with mixed feelings. I only have the Thermalright Venomous X to compare the K2 cooler with. And even though in the boxed version and hooked up to the PWM fan controller it manages to equal the VenomousX in performance (with low 1100RPM fans). If we allow the fans to spin up to max RPM (via disabling the PWM control)  it comes close to the dual fan 2000rpm VenomousX again. Going triple fan unleashes even a tiny bit more performance. So what's the issue then ? This coolers dissapation surface is far bigger then that of the VenomousX, so why isn't it outperforming the dwarf cooler ? Firstly the compromise Alpenföhn always makes is noise versus cooling performance. And there the K2 shines with it's two included fans. Under PWM control they are hardly audible. Letting them run maxed out, makes them a bit more audible, yet significantly improve the cooling performance. Don't worry about the generated noise, as usually your GPU or case fans will be louder. Secondly if you look at the bottom plate of the K2 versus the VenomousX you spot a huge difference in size. We have no idea if the two outer heatpipes are really effective as they have got no direct contact with the CPU.

 

 

 

There were two some small installation woes on my particular testbed. The Asus Rampage 3 Extreme board is running normally with the optional taller IOH chipset heatsink and small fan. Due to the K2 dimensions I had to replace the IOH cooler with the original smaller one. Increased chipset temps as a result. Secondly only low profile dimms can be used with this cooler. Which is a real setback in my opinion. To be able to use my Corsair Dominator kit I had to remove the top heatspreader part. This really should be corrected by Alpenföhn as it can be one of the differences to buy or not buy this cooler. Okay they put up a ram compatibility list, but that's not really cutting it.

 

 

Retailing at similar prices as other top end air cooler around the 75-80 euro mark. This K2 twin tower cooler might not be the best performing one, though it's looks can surely persuade many to give this one a go. If only the K2 had cooled better on the PWM setup, than the VenomousX cooler then a performance award would have been well deserved. Yet due to the high quality finish, solid mount, the two included great WingBoost fans and last but not least the good cooling performance versus noise ratio : we still award it with a high end label.

 

 

PROS :

• very good performance/noise ratio
• maximum socket compatibility, including LGA2011 (free upgrade)
• very solid fixation
• two included silent WingBoost fans
• If looks could kill...

 

CONS :

• ram compatibility

 

I wish to thank Vahid from CaseKing.de for the review sample.