Spire Gemini Rev. 2 review

Adequate in a crowded market is just not good enough

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The last two active CPU coolers we've tested, the DeepCool Fiend Shark and the excellent Enermax ETS-T40-TA, put in impressive showings in both the important cooling tests and how quickly they were able to return to their idle temperatures.

Against those two the Spire Gemini Rev. 2 was on a hiding to nothing.

Using the same Z68/2600K combo both the other coolers had the Gemini Rev. 2 beat hands down. The Enermax cooler - with only a single fan and two fewer heatpipes, remember - manages to consistently sit around 7degrees cooler than the Spire.

That's both at idle and 100% CPU loads.

The Gemini Rev. 2 is also much slower to return to the idle temperatures. The Enermax cooler drops back from its height of 50degrees back down to 20degrees in less than two minutes. The Gemini Rev. 2 though took around five minutes to get back from 57degrees down to 28degrees.

Spire Gemini Rev 2
Decent cooling, but there are better options around

In its defence it did manage to get close after around three minutes, but still took another couple of minutes to chill out those last few degrees.

That's not to say the cooling the Gemini Rev. 2 offers is not adequate for a high-performance CPU, it absolutely is.

In fact compared with the Corsair H100 liquid cooler that generally sits atop our test bench it wasn't far short of that chiller's chops. It was only one degree hotter at 100% load and had the same idle performance.

The Corsair H100 though zips back to its idle temperatures faster than any other cooler we've seen, dropping back to idle in 99 seconds flat.

But it's not all about straight performance; there's little more annoying than fitting a new cooler with bleeding fingers.

The Gemini Rev. 2 though is beautifully machined so there's no sharp edges to slice through your delicate epidermis, but that doesn't mean it's not an awkward bast to fit.

It may have attachments for all sockets, but that universal approach makes for fiddly fitting. With the twin fan setup you're also cutting out the closest DIMM slots to the CPU socket.

So while it's an effective cooler, the Spire Gemini Rev. 2 is off the pace in both ease of use and straight line cooling performance.

It's still the Enermax ETS-T40-TA all the way.

We liked

The Spire Gemini Rev. 2 gives decent cooling performance for an average air-cooler and it's also universally able to fit on any desktop CPU socket you want to throw it at.

We disliked

Unfortunately that doesn't make it particularly easy to actually fit onto your chosen socket.

The average performance too means that against the much better competition this cooler is off the pace at the top. And the top air-cooler is around the same price too.


A decent contender, but the average performance doesn't cut it in the crowded chiller marketplace.

Tech Specs

Product TypeCooling Fan/Heatsink
Number of Fans2
Compatible Processor SocketSocket H LGA-1156, Socket H2 LGA-1155, Socket B LGA-1366, Socket AM2+ PGA-940, Socket T LGA-775, Socket 939, Socket AM2 PGA-940, Socket AM3 PGA-941, Socket FM1
Fan Speed2 x 1650 rpm
Brand NameSpire
Connectors4-pin PWM
Air Flow2 x 71.1 CFM
Product LineGemini
Fan Diameter2 x 120 mm
Green CompliantYes
Green Compliance Certificate/AuthorityRoHS
Heatsink Height153 mm
Heatsink Width71 mm
Heatsink Depth131 mm
Fan Bearing TypeBall Bearing

Intel Processors:

  • Core 2 Duo
  • Core 2 Extreme
  • Core 2 Quad
  • Core i3
  • Core i5
  • Core i7

AMD Processors:

  • Athlon
  • Athlon II
  • Athlon X2
  • Sempron
Product ModelSP986B1-V2-2P
Product NameGemini Rev.2 - SP986B1-V2-2P
Package TypeRetail
Manufacturer Part NumberSP986B1-V2-2P
Manufacturer Website Addresshttp://www.spirecoolers.com
Marketing Information

Gemini Rev.2 is the Zodiac sign for the twins. We have codenamed our newest high-end thermal solution due to the two towering dimpled fin heat-sinks. Gemini is the ultimate evolution of the hugely successful TherMax cpu cooler series. The increased number of heat-pipes combined with a higher number and density of dimpled fins and crowned with two (2) high airflow fans for extreme cooling performance. Six (6) U-shaped 6mm heat-pipes are in contact through the solid copper base with the CPU, rapid heat transfer to the 52 aluminum dimpled fins providing a larger surface area for optimum heat dissipation. The Gemini Rev.2 is supplied with two (2) 12cm balanced DC fans providing high airflow and sufficient cooling. Compatibility is guaranteed with multi-platform mounting for all current Intel and AMD micro-processors. The Gemini is pure cooling power that takes performance to the level. Spire - Powered by Innovation.

MaterialCopper Base, Aluminium Fin
Weight (Approximate)842 g