HardwareHell

Introduction
Once again I have a new product on my desk for evaluation. The GeminII Heat Sink from Cooler Master is similar to Toyota entering the NASCAR Circuit, you know Toyota is a good car manufacturer; you just never put the two together. Same with Cooler Master, you know they make good cases (I’ve always loved their line of Stacker cases), but I had never actually considered them in any of my cooling choices before. They did get my attention with the Hyper TX, but it was still more of a medium performer. Well, I’m here to tell you that Cooler Master has been doing their homework. This piece of metal has High-Performance written all over it like stickers on a race car, even the box is pretty.




This is a large Heat Sink with the overclocker or silent pc enthusiast clearly in mind. A large case is a foregone requirement. The small form factor has been banned from the race track. This Heat Sink sports a $50 price tag on it but you’ll need a couple 120mm fans to go with it. So count that into your budget when you go to place your order.
I’ll be testing this Heat Sink with (3) different combinations of fans to provide a clear picture of what can be expected with your purchase. I polled some of my friends and decided to use Nexus, Silverstone and Delta’s for this evaluation.

Features
The following features are clearly listed on the box.

• - Compatible with AMD X2 Dual Core, Intel Core 2 Duo and Core 2 Extreme.
• - Fan Bracket design for mounting two 120 mm fan cools CPU and its surrounding components (VRM, Memory, Chipset, and etc).
• - Flexible bracket design provides interference-free installation.
• - Copper base with 6 heat pipes design creates superior cooling performance.
• - Huge aluminum fin design for excellent heat dissipation.

Specifications
The following specifications are provided by Cooler Master and clearly listed on the box.

• - CPU Socket: Socket AM2/754/939/940/LGA775
• - Heat Sink Dimensions: 175×124.6×81.5mm
• - Heat Sink Material: Al Fin + Copper base + 6 Heat Pipes
• - Weight: 847g
• - Thermal Resistance: 0.17o C/W (with Cooler Master fan: R4-S2S-12AK-GP
  or R4-S2B-12AK-GP) 
• - Noise: 20.7 dBA (with Cooler Master fan: R4-S2S-12AK-GP or R4-S2B-12AK-GP)

Applications
The application of this heat sink is clearly labeled on the box as

• - Socket AM2/754/939/940/LGA775

And a complete compatibility chart is visible on the side of the box.

Test Setup

• - Intel Core 2 Extreme X6800 (engineering sample)
• - EVGA 680i SLI mobo
• - Corsair 2x 1GB XMS2 PC2 8500
• - (2) XFX 7950 GX2
• - PC Power & Clg. Turbo-Cool 1Kw Power Supply
• - Cooler Master CM Stacker Full Tower Case
• - Windows Vista Home Premium 32bit
• - UEI DT200 Digital Thermometer

As I stated earlier I’ll be testing this Heat Sink with (3) different sets of Fans. Here are the basic specifications on each fan I have chosen.
Nexus DC Brushless Axial Flow Fan D12SL-12

• -Dimensions: 120×120x25mm
• -Weight: 123 grams
• -Voltage: 12 Volts
• -Rotation Speed: 1000 RPM
• -Acoustic Noise: 22.8 dBA
• -Air Flow: 36.87 CFM

SilverStone FM121

• -Dimensions: 120×120x25mm
• -Weight: 160 grams
• -Voltage: 12 Volts
• -Rotation Speed: 800-2400 RPM
• -Acoustic Noise: 17 dBA at 800 RPM, 39.5 dBA at 2400 RPM
• -Air Flow: 110.03 cfm at 2400 RPM

Delta FFB1212EHE

• -Dimemsions: 120×120x38mm
• -Weight: 410 grams
• -Voltage: 7-13.2 Volts
• -Rotation Speed: 4000 RPM
• -Acoustic Noise: 59.0 dBA
• -Air Flow: 190 cfm

Installation
It should be noted that this Heat Sink may not support some of the vertical socket type Motherboards. I have seen a few pictures from other sites where the Heat Sink was successfully mounted in the vertical position. But because of a lack of clearance with my chipset cooler I could only mount this Heat Sink in the horizontal position.

And this is a very Heavy Heat Sink, care must be taken not stress your Motherboard while installing and handling it once it’s attached. You could very easily damage your motherboard with careless negligence. Enclosed with the Heat Sink is a little booklet containing the user manual/installation instructions. The lettering and illustrations are small and hard to read, you may need to break out your spectacles. Basically, this is a 10 step process. Steps 1-3 require you to attach the correct retention plate to the Heat Sink depending on your CPU type. Step 4 is the application of Thermal Paste to your CPU. Steps 5-6 require you to physically attach the Heat Sink to the Motherboard. Step 7 is attaching your choice of fans to the fan bracket. Step 8 is attaching the fan bracket to the Heat Sink itself. Step 9 is to adjust the location of the Fan Bracket Assembly on the Heat Sink. As the following pictures show, the Fan Bracket slides from side to side. This allows for an interference free installation with your other components.

Step 10 requires you to plug in your fans to the appropriate power connector. At this time a pdf version of this manual is unavailable from Cooler Master which I find disappointing. I truly expected Cooler Master to have all the “Bells and Whistles” available with the release of this product.
Here are some pictures of the GeminII before it is installed. Note the lack of a lapped mirror finish on the copper base.

Test Results
I obtained all of these results running my system overclocked at 3.35 GHz with 1.4 Volts. Idle temps were taken after 15 minutes of inactivity. Load temps were taken after 30 minutes of running the Folding@Home consule 5.04 and Prime95. http://folding.stanford.edu/download.html and http://www.mersenne.org/freesoft.htm

Conclusions
Well the race is done and the Cooler Master GeminII has crossed the Finish Line in 1st Place in my record book. This is easily the Best Performing Heat Sink I have ever laid my hands on. Whether you want fast quiet computing or loud “NASCAR” riding on the edge computing, this is the Heat Sink to take you to the
Winners Circle.

Summary
Pros:

• - High-Performance
• - Multiple CPU Compatibility
• - Adjustable Fan Bracket
• - Choice of Fans
• - Intimidating Appearance
• - Competitive Pricing

Cons:

• - Very Large. This won’t fit in a lot of small and medium size cases
• - Very Heavy. Hit the Gym before going to any Lan Parties.
• - Expensive. Though competitive with similarly classed Heat Sinks.
• - Manual is hard to read. No online .pdf file.
• - Cooper base is smooth and shiney but lacks a lapped mirror finish.
• - Motherboard must be removed for installation and maintenance.

If I was rating this as a standard hardware product it would not score that well. But the fact is this is not your standard product. It was Designed for the Enthusiast and most of the Cons simply do not apply. I’m rating this a 9 out of 10 for the WIN.