Scythe Mugen 5 Rev.B CPU Cooler Review

Early Verdict

Moderate cooling performance, but otherwise a high quality CPU cooler. The Scythe Mugen 5 Rev.B is a great buy for those looking to reduce noise in their rigs.


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    Very quiet stock fan

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    Pricing (can find deals for $45 dollars as well)

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    Moderate cooling


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    Moderate Cooling

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Features & Specifications

The Scythe Mugen 5 Rev.B (SCMG-5100) adds AM4 support to a previous cooler model that we haven't tested yet (SCMG-5000). Both versions use a single large heatsink and a single 120mm low-speed fan to improve cooling and lower noise.



Within the box, you’ll find the heatsink, a 120mm stock fan, mounting brackets for the cooler, the owner’s manual, a long screwdriver, and thermal paste. Bracket options include every standard available from Intel and AMD motherboards, including the AM4 socket. The Mugen 5 also comes with a manufacturer’s two-year warranty.

The cooling pipes are plated the same color as the rest of the cooler, giving it a uniform silver finish across the surface. The fan is a matte black color. Those concerned with color coordination should find it a safe bet to go with many different build themes. The CPU contact surface is smooth and reflective. There’s plenty of room for airflow in between the heatsink's largely spaced out slabs. Six heat pipes support the CPU contact plate.

Brackets are easy to install with a screwdriver, and they are sturdy. An included plate that fits behind the socket of LGA 1150 through 1366 motherboards is not necessary in our LGA 2011-v3 system. The screwdriver is extra long to reach the spring-loaded screws at the base of the heatsink, securing it to these brackets. Fitting the fan to the heatsink requires some hand coordination, as the kit includes skinny metal clips to secure the fan. But the fit is secure, even with the small clips.

With the fan installed, it’s important to be aware of the cooler's 0.36” offset. If this offset interferes with some of the motherboard connections, the heatsink can be installed in the other direction. We didn’t experience this issue, however.

There's a small graphic logo featured on top of the heatsink, which would look good installed in either direction. The studs coming out of the heatsink add a nice aesthetic touch.

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  • AgentLozen
    I'm getting a "file not found" error when I attempt to access page 2.
  • shrapnel_indie
    I presume this all falls down to the fan. Replace the fan with its, more than likely, cheap sleeve bearings with a better fan, and the 1 year issues will start to weaken. Of course that will probably increase noise and improve cooling performance... depending on the replacement... but once this is done, you've just spent more $$$.

    Sell just the Heatsink for around $30-40, and let us choose our own fan to buy? Then we fall responsible for its noise/performance ratio. Toms, would be nice to see these heatsinks done and compared also with a specified fan of the given size (ie. Noctua NF-A12x15 PWM for a 120mm fan, or other agreed upon model)... just to even out what the heatsinks alone can do (cooling performance, and its own contribution to noise, subject to fan blade design.)
  • dstarr3
    19815117 said:
    I'm getting a "file not found" error when I attempt to access page 2.

    I'm getting that on a lot of Toms pages lately. Just refresh until it works.
  • BadBoyGreek
    I've stayed away from Scythe coolers since the Ninja 2. Had installed it in a friend's rig some years back and within a year, the fans failed 3 times. You also had to install the fans after the heatsink was secured to the mobo, otherwise you wouldn't have enough clearance to fasten it to the socket otherwise, and the retention clips / fans were a pain to install after the fact.

    Perhaps Scythe coolers have improved since my experience with them, but based on past experience, I wouldn't recommend them.
  • Bsquared
    I have to yell out a "yeah, me too!" to what SHRAPNEL_INDIE said. I would indeed find it very useful to see a test of a group of heat sinks all being tested with the same fan. That would really empower us, the "poor" enthusiasts. It would be nice to know for once that we could overclock to our hearts' content with the potential of not needing to spend double on an AIO for every build.
  • the nerd 389
    Is there any way you could check the minimum sustainable fan speeds? Just knowing how slow they can go would help in designing a quiet build, especially for the coolers with higher max speeds.

    After all, the best cooler for quiet builds is one that has decent performance at slow fan speeds as well as enough headroom to push the CPU when needed. This cooler is quiet, but I wouldn't want to run the CPU at 85 C (61+24C).
  • Onus
    Each cooler review I've seen over the last year or so just makes that cheap Gammax look better and better. Slowing its fan down, or using a better fan, would likely quiet it down nicely while still providing decent cooling performance.
  • the nerd 389
    19815980 said:
    Each cooler review I've seen over the last year or so just makes that cheap Gammax look better and better. Slowing its fan down, or using a better fan, would likely quiet it down nicely while still providing decent cooling performance.

    If you replace the fans on this cooler with faster models with similar airflow and noise at a given RPM, it would outpace the Gammaxx 400 in all realistic cases. This is based on the measured values in the article and a 40*log relationship between the delta-T and noise (usually quite accurate for estimating cooler performance).

    Based on that model, this cooler even gives the NH-D15 a run for it's money. The D15S would probably turn out ahead, though.
  • systemBuilder87
    I think anybody looking for a quiet fan will probably buy a Noctua U14-S (140mm fan) which moves at least 40% more air at the same RPM, so it can run at much lower RPM. We recently got one shipped from Amazon for $70 including tax ($64 retail). I think it would be a better cooler and potentially, just as quiet. It is low profile and can fit into many cases.
  • Ltpessimist
    I have Scythe Zipang it also takes upto a 140mm fan, i have a noise blocker fan on it now and i think it is one of the most robust cpu coolers of it's time. got it about 9yrs ago and it still fits all sockets including the new Amd AM4 socket. so if my cooler is this good maybe this new one will be even better.