EKL AG (Elektronik Kuhlsysteme Leutkirch GmBH ) is an ISO9001 thermal solutions company based in Leutkirch Germany which specializes in manufacturing OEM heatsinks for the European market. The company has been making in-roads into the enthusiast markets, and the latest example of what it has to offer is the EKL Alphenfohn GroB Clock'ner heatsink. As you've probably already realized, other vendors like Sunbeamtech have virtually identical heatsink models available.

The Alphenfohn GroB Clock'ner heatsink on the test bench today is a heatpipe direct contact cooler - meaning the heatpipes are exposed at the base. EKL's heatsink stands 154m tall, is 125mm across and weighs upwards of 700grams. The unit makes use of simple wire clips to hold the standard 120mm fan in position, and it spins at a fixed speed of 1200 RPM (non-PMW). The heatsink is compatible with Intel socket 775 and AMD socket 754/939/940/AM2 processors, as of this writing socket 1366 is not supported.

The Alphenfohn GroB Clock'ner should fit most full and mid-tower PC chassis, but may be too tall for some microATX systems, so keep that in mind as you scan through Frostytech's review. Installation is entirely tool free, and refreshingly the motherboard doesn't need to be removed to install the mounting bracket. Its retail price is expected to be in the region of $40CDN ($40USD).

EKL Alphenfohn GroB Clock'ner Heatsink

heatsink specsheet manufacturer: ekl model no.: grob clock'ner Materials: aluminum fins & base, copper heatpipes Fan Mfg: YS Tech KM121226LS Fan Spec: 1200RPM, 12V, 0.18A Fan Dim: 25x120x120mm Heatsink & Fan Dim: 154x125x104mm Weight: 718 grams Includes: Mounting bracket, thermal compound, fan speed controller, instructions Compatible with Sockets: 754/939/940/AM2/AM2+, 775 Est. Pricing: $40USD ($40CDN)

The technique of using large diameter copper heatpipes in direct contact with the top of the processor minimizes thermal joint resistance. Heat energy is conducted directly to the heatpipes, instead of through a base or questionable solder joints. The method works extremely well with heatspreader capped processors that generally have larger silicon dies.

Installation Hardware

EKL's Alphenfohn GroB Clock'ner heatsink is compatible with Intel socket 775 and AMD socket 754/939/940/AM2/AM2+ processors. The heatsink has one common clip attached to the base which operates in a tool free manner. The clip is designed with AMD socket 939/AM2 CPUs in mind, so for Intel processors a specialized heatsink retention frame needs to be installed. The black adaptor pops into the four holes around the Intel processor socket, and then all the user has to do is push in four plastic pegs to expand the feet and lock the retention frame into position on the motherboard PCB.

The system is a modified version of the standard Intel push-to-click heatsink attachment mechanism, and has the benefit of clamping firmly in place without requiring the user to remove the entire motherboard first and fiddle with screws. An illustrated manual provides guidance, and a fan speed controller and syringe of thermal compound are also provided.

FrostyTech's Test Methodologies are outlined in detail here if you care to know what equipment is used, and the parameters under which the tests are conducted. Now let's move forward and take a closer look at this heatsink, its acoustic characteristics, and of course its performance in the thermal tests!