Thermalright AXP 100RH & 6850K CPU

Hello everyone,

I've bought the Thermalright 100RH cooler simply for its small factor (not blocking RAM slots), claimed great cooling capacity, and being very low on weight. I didn't know what to expect before connecting it to an Intel 6850K CPU in my new rig.

Not really sure if I'm doing/have done something wrong but my CPU keeps up very hot at Idle and minor load, like in the 59-61 degrees Celsius range. I didn't really dare to benchmark it /push it to its limit for long as I was afraid it will go, so tested it with Aida with the same cooler for 10 minutes only under 100% load. It didn't reach more than 75 degrees with the cooler's fan running at 100%.

Per-core temperatures at idle/minor load in Windows are 45-48 degrees Celsius, CPU is not overclocked, normal clock frequency generally stays below 2GHz, still CPU package temperatures are around 60 degrees. I tested under different CPU fan scenarios as most of the time these reported temperatures are monitored under between 1300 and 1450 CPU fan RPM.

My motherboard is ROG Rampage V Edition 10 with latest BIOS and 32GB Corsair Vengeance DDR4 RAM, running at 3200MHz set directly at its default XMP mode in the BIOS. Most BIOS CPU options are set to Auto with Sync All Cores option and Intel Virtualization Technology on. If I run the RAM at its motherboard's default 2133MHz value CPU temperatures go down by about 8-10 degrees, still they are too hot at idle anyway.

Case (Corsair 650D) is very well ventilated (and with excellent cable management) with room air temperature about 20-22 degrees. I have a M.2 drive installed on the motherboard that keeps 40-41 degrees most of the time, graphics card stays about 29-30 at idle, all other measured components temperatures are lower.

What could be the problem that I'm getting these high CPU temperatures? I'm using Gelid Extreme thermal compound, the cooler makes good contact with the CPU, I even removed the cooler, reapplied thermal compound again, fitted it over again, tested, turned the fan in reverse, but CPU package temperatures remained around the same. These temperatures were measured with Aida, HWiINFO and Corsair Link. Aida is reporting the highest CPU package temperatures (4-5 degrees higher than the others) but the rest of the measured temps by all programs are exactly the same (including per CPU core). OS is Windows 10 but even before entering it, the BIOS reports similar CPU temperature.

The cooler itself is https://www.amazon.co.uk/Thermalrig...471508&sr=1-1&keywords=Thermalright+AXP+100RH

Any suggestions would be highly appreciated. Thanks.

You're reaching the cooler's limit of performance. The cooler's max TDP is 180w, the chip is 140w @ stock. You can try swapping fans to something that has more pressure, but that will result in more noise. What is happening is the type of cooler the TR is. It's actually blowing the how air downwards on the board. You would do better with a Tower style cooler to get the heat away from the board and out of the case.

A good example is the Noctua NH-D15 or the CM Hyper 212 Evo.

Simply put, the cooler you have chosen is inadequate for the CPU. It has a TDP of 140W right out of the box, only 40W less than the TDP rating of the cooler.

Having said that, I would note that none of the temps you have quoted are even close to the danger range. The CPU will not throttle down until you get to about 100c. And the fan speed of the cooler has a max of 2500 rpm so the fan speeds you report are much less than that. So the cooler has some reserve cooling power that hasn't been tapped yet. But if you push it it will do so at the expense of higher fan noise.

What is your fan speed profile set to? If you set it to Performance or full speed you might get lower idle temps but more fan noise.

Seriously, though, there are a million big tower coolers that you could have chose that wouldn't present a problem with RAM clearance. Many of the manufacturers intentionally design their high end coolers with this in mind, like the Noctua NDH 15 for instance. I'm kind of scratching my head as to why you chose that little small form factor case cooler when there are so many good big boy cooler options out there.

The cooler you have now is designed for mini ITX cases, not for 6800k Broadwell work station applications.

You should also look at an AIO water cooling solution. That would eliminate all problems with RAM clearance.

Thank you very much guys.

I've chosen this cooler simply because I didn't want "fortresses" inside my case hoping that the active internal ventilation will get things right, especially at idle. In the end, the 100RH is designed for pretty limited cases so I was hoping to compensate with space/fresh air inside. It was like "I know I may be doing the wrong thing but I must prove that I will be wrong first".

Now, based on your experience, what would be the best air cooler to choose for the 6850K with the idea for some future (not extreme) overclocking? I know many guys who went wrong with water cooling damaging motherboard and other components so prefer to stay safe and continue with an air-based one. Also some reviewers arguably claim some of the best air coolers keep on par with the water ones.

Before going for the 100RH I was considering Deepcool Assassin II, Thermalright True Spirit series, Be Quet (...) Rock, CM and more. Noctua is probably the best choice but I didn't want the brownish fans inside my case - which is black and red mostly. Another requirement was fan noise ideally below 28dB under full load and tower type, i.e. not blocking RAM slots.

Now I am angry with myself spending so much on this cooler while able to get something much better for like 80% of its value. I even contacted Thermalright just to be sure fan change would make any difference. They requested specific details being aware which CPU I was referring to in the very beginning, wating for reply.

I am now changing it anyway so would appreciate your advice on what would fit best my CPU, preferably not too big and silent tower one. If the colour scheme is not matching I'd possibly change the fans later.

I am afraid if you insist on staying with air you will have to put up with a "fortress" in order to adequately cool that 6800k. All of the coolers you mentioned would be good choices but some of them may indeed present a clearance issue with the RAM so you can't totally forget that.

But I disagree with you about the risks of an all in one water cooler. A higher end one will give you as good or a little better cooling than the best air coolers and will avoid the fortress and RAM clearance issues. Actually, leaks and ruining equipment are very rare with AIO water coolers. And pump failures seldom ruin modern CPUs because of all the thermal shutdown protection technology in place.

But I do hear you about the fortress issue. That's exactly why I moved over to water cooling. Really opens up the case and makes things easy to get to.

My AIO keeps my OC'd 6700k (4600 MHz) @ 28C or thereabouts. No leaks, very little noise. My rig sits about 4 feet from me and I can't hear it.

I have a coolermaster seidon 240M that has been running 24/7 for a long, long time, no issues with that thing.

Alaric said:

My AIO keeps my OC'd 6700k (4600 MHz) @ 28C or thereabouts. No leaks, very little noise. My rig sits about 4 feet from me and I can't hear it.

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Frankly speaking I never had a liquid cooler (air ones were good enough in this case) so am cautious when it comes to using them. Probably I shouldn't but only opening your Deepcool Captain cooler's product page on Amazon I've seen three recent comments on the main page referring to leaks and failed pumps, https://www.amazon.co.uk/DEEPCOOL-C...93494659&sr=8-1&keywords=Deepcool+captain+360. Also, my rig is in a bedroom so I must keep the whole thing as quiet as possible which with some of the liquid coolers is really impossible.

I still may go for one or with a small tower air cooler. Still thinking over. Thanks a lot for all your comments.

If you're going to go with a more modest air cooler I might suggest the Cryorig H7.

paraiso said:

Frankly speaking I never had a liquid cooler (air ones were good enough in this case) so am cautious when it comes to using them. Probably I shouldn't but only opening your Deepcool Captain cooler's product page on Amazon I've seen three recent comments on the main page referring to leaks and failed pumps, https://www.amazon.co.uk/DEEPCOOL-C...93494659&sr=8-1&keywords=Deepcool+captain+360. Also, my rig is in a bedroom so I must keep the whole thing as quiet as possible which with some of the liquid coolers is really impossible.

I still may go for one or with a small tower air cooler. Still thinking over. Thanks a lot for all your comments.

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Because of all that it's not worth messing with kinda and your limited more too with case options and mounting if you wanted to run a case anyways more specific to fit the rad in there and mounted up. Go High end air and like some of the best thermally rated tims you can get a hold of mount up and forget about it.

trents said:

If you're going to go with a more modest air cooler I might suggest the Cryorig H7.

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The Cryorig H7 is not designed for LGA 2011(-v3). My CPU is Intel 6850K. Its TDP is also only 140W.

140W TDP does not take into account overclocking. If you overclock it to its ambient air limit it will reach 200 watts or more easily. Give yourself some headroom.

Exactly. What do you think of the new Scythe Mugen 5 SCMG edition, http://www.scythe-eu.com/en/products/cpu-cooler/mugen-5-pcgh-edition.html.

It's been released a few months ago and looking at real users' YouTube videos, it looks much better than what I have now. Unfortunately I couldn't find TDP data. No RAM clearance issues from what I can see and very silent.

Or if you have any more specific suggestions, please do let me know. I decided I'm staying with air cooling.

At a weight of over 1000 gms it should soak up a lot of heat. Sycthe has been making coolers for a long time and has produced some classics over the years. I don't think you could go wrong with this one as long as you are sure it won't present RAM clearance problems. Just for future reference, I purposely avoid RAM with tall fins so I won't be limited in choosing coolers. It's been proven by testing that the heat spreaders and fins they put on RAM do little for cooling and mostly are just eye candy.

But I cannot find a USA vendor who carries that cooler. Are you outside of the US?

paraiso said:

Exactly. What do you think of the new Scythe Mugen 5 SCMG edition, http://www.scythe-eu.com/en/products/cpu-cooler/mugen-5-pcgh-edition.html.

It's been released a few months ago and looking at real users' YouTube videos, it looks much better than what I have now. Unfortunately I couldn't find TDP data. No RAM clearance issues from what I can see and very silent.

Or if you have any more specific suggestions, please do let me know. I decided I'm staying with air cooling.

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Like 200-300w? I don't know all the monsters and beyond yeah suppose to be 350w++ capable, but yeah better hope you don't have dims with a tall spreader you'll have to move them or only able to run like a few in the back and just barely not hit on the fans.

The design of that Scythe cooler you reference is asymmetrical so if you have RAM installed on both sides of the socket then you might have RAM clearance issues to the back.

trents said:

The design of that Scythe cooler you reference is asymmetrical so if you have RAM installed on both sides of the socket then you might have RAM clearance issues to the back.

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yeah that looks fine clearance wise, something like d14/15 might be a concern had to move the tall dims in the back just no way with that thing and just barely cleared.

trents said:

At a weight of over 1000 gms it should soak up a lot of heat. Sycthe has been making coolers for a long time and has produced some classics over the years. I don't think you could go wrong with this one as long as you are sure it won't present RAM clearance problems. Just for future reference, I purposely avoid RAM with tall fins so I won't be limited in choosing coolers. It's been proven by testing that the heat spreaders and fins they put on RAM do little for cooling and mostly are just eye candy.

But I cannot find a USA vendor who carries that cooler. Are you outside of the US?

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I agree about RAM heat spreaders being more decoration than any cooling solution, but they are beautiful and look amazing, especially with LEDs. I have the red LED Corsair Vengeance DDR 4 version and it looks just lovely, especially when it's darker. Also I adjusted the motherboard LEDs to match the RAM leaving a red-like lighting all around the motherboard parts, which together with a 200 mm. Spectre white LED front fan and a USB 3 card reader just below the blu-ray drive with a red LED when the system is on, creates a lovely red-and-white appearance, both on the front and when looked from the top/side. Some people like such things, some don't. I personally do, to the extent all parts have their own personality (and not being just a bunch of dark impersonal PCBs).

I live in the UK so it's easier to buy it in Europe. In the UK it's about 80 pounds which is too expensive (compared to other EU countries) so I am most probably going to buy it from Germany (where Scythe is very popular and they have much more supply) almost twice cheaper. Here's another review, http://www.gamezoom.net/artikel/Scythe_Mugen_5_PCGH_Edition_Test_Review-38646-0#, it's in German - just click on nächste Seite (next page) at the bottom right and you will see the temperatures and later on the noise emitted compared to other air coolers. I think it presents itself pretty well.

RJ88 said:

Like 200-300w? I don't know all the monsters and beyond yeah suppose to be 350w++ capable, but yeah better hope you don't have dims with a tall spreader you'll have to move them or only able to run like a few in the back and just barely not hit on the fans.

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At the moment I only have 2 x 16GB Corsair Vengeance slots taken - 2nd from the CPU cooler on both sides. This 3.2GHz (or higher) XMP memory is still quite expensive so I am planning to buy another 2 of the same later on. 64GB should be pretty much enough for everything for years to come. With the heatsinks it's 50 mm. tall so hopefully it will go beneath. The heatsinks can be removed and I have 8 RAM slots on the motherboard anyway.

My current Thermalright's cooler fan is now running at about 70 to 80% at all times to keep my CPU package temperature at 50-55 degrees Celsius at about idle. I need to change it ASAP and with air coolers I don't have many options. I've been going through dozens of different coolers and reviews over the past few days and they are either too heavy, or too loud, 90%+ present RAM clearance issues by default, or are heavy and loud - and still very ineffective at the same time. So, if I am to make sacrifices with RAM, let it be. At least I will be able to use my PC without permanently looking at the temps

So I'm confused by your last post, especially by concern about "heavy." The Scythe you reference is no light weight cooler. Are you still planning to go with that one? Honestly, the only time I have ever heard of a heavy cooler breaking a motherboard on this forum (and I have been active here for a number of years) was some guy who had a gaming PC built by some company and shipped to him. So unless you are traveling and taking your rig with you I don't think it's an issue.