Mugen 2 Cooling Fan at a constant 200RPM?

Hi there,
For some reason, my Scythe Mugen 2's main 120mm scythe fan is only reading 200RPM in HWmonitor.

I'm using an i7 920, and even during times of load (temps go to around 65'C), the fan speed fluctuates between 175 rpm and 210 rpm.

I thought the fan was suppose to go up to 3000RPM? Anyways, I have it plugged into my mobo (Intel DX58SO), while my other fans are plugged into the power supply.


Is this a fan error, or am I somehow not reading HWmonitor correctly? (maybe it's the mobo chipset fan?)



Btw, are my idle temps a bit high for the Mugen2? It's 72'F in the room, and I've heard the i7 idles at mid 30s with stock.

What you really should be concerned with is load temps. What you have listed seems a pretty good too me but there are a ton of things that go into your CPU temps. Case, other fans, etc. I have a mugen 2 and dropped my case temps 10 C (@ load) by replacing my case fans. I get around the same as you are at load. Before my case fan replacement I was getting 65 C @ load stock.

Btw, as for my idle temps...perhaps I applied too much thermal paste? Is this idle temp normal for Mugen2s (I couldn't look up that many online with comparable systems)


Should I reassemble my entire PC and reapply the thermal paste?

There's no need to reassemble your whole PC, but make sure you did install the HSF correctly. It shouldn't move at all aside from the weak mounting.

What thermal paste are you using? If it's Arctic Silver 5, give it a week or two to burn in, and you'll definitely see the difference. All you need is about the size of 2 grains of rice and you can spread it out with an old credit card or something similar.

As for the Mugen 2, it actually only goes up to 1300 RPM, even says so on the box. Check your BIOS setting for smart fan control and turn it off, if it's on. Otherwise, try using another program like Speed Fan to manually increase the fan speed.

This is just with a single stock Scythe Mugen 2 fan.

Edit: Oh and depending on the room temps, I usually get low-mid 30C to low 40C for stock settings on my PII 955.

Ok, I'mma try out your suggestion.

Although it's strange that even with smart-fan on, it doesn't even go above 200RPMs during load.

Also, is your 29'C cpu picture with an i7 920 or Phenom2?


The Mugen2 is the type of cooler that is attached from the bottom of the motherboard...so you basically need to reassemble everything if you want to tighten it. But I checked and the HSF is perfectly firm.

Phenom 2, but yeah when I was researching for a good CPU cooler I saw a lot of people having the auto-fan problem. The mobo isn't perfect at detecting things, so you'll have to manually tweak things if something is wrong.

I was happy that my mobo has a clear cmos button, so if I ever mess up with my settings I can just go back to the default and reload any saved settings in the past. Cheers for the people who thought of putting buttons on the mobo.

You can with Speed Fan, but the stock fan still caps at 1300RPM, which is still silent.

A lot of people like to put the slipstreams with 100+CFM here, but it is VERY loud.

Speed fan works great it just takes some time to configure.. For example, go to the big "configure" button on the right, and change the fan speed %'s and desired temps for all components.. took me a while when I first started to tweak it but now that I got it set up I love it.

But for some people it unfortunately just has problems =( hopefully that isn't you so you don't miss out on a great tool.