• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Comparison of AS5 vs. MX-4 on Haswell i7-4790K

graysky

Senior member
I compared Arctic Silver 5 to MX-4 between my new i7-4790K and my NH-14D. In short, I ran mprime (Linux64,Prime95,V28.5,build 2) using large FFTs with 8 threads and logged the temps throughout the run once per second using a shell script. Ambient temp which is very important to consider did not vary more than 2 F since the system was placed in my basement where it is very consistent. The digital thermometer showed 59F as the low and 61F as the high which is approx 1 C.

Run 1 was Arctic Silver 5 which had cured for approx 52 hours. I ran mprime as noted above for 4 hours.
Run 2 was with MX-4. I ran mprime as noted above for approx 1-1/2 hours.

Histograms in blue show the temperature distributions for AS5 and those in pink show the same for MX-4. The solid black line for each core is the average temp for each core. You can clearly see differences between the two of 2-4 degrees (allow for +/-1 C due to the ambient temp range). AS5 was the superior TIM in the test experiment.

Test system
Processor: i7-4790K @ 4.40 GHz (vcore 1.232 volts under load)
HSF: NH-14D with 120mm and 80mm fan running at max
Motherboard: MSI Z97 MPOWER MAX AC


EDIT: I have to totally invalidate my findings based on a configuration oversight: it seems that $HOME/prime.txt on linux dictates what size FFT mprime uses. I have found that using "large FFTs" as I did the the experiment allows for values of 128k-1024k which is a range that causes a given CPU various levels of stress. The trend is for smaller values to give more stress and as a result, higher heat. In short, I have no way to go back and see which FFT size prime was using when I compared these two. Here are my findings using the same TIM, but varying the FFT size. Each run is a average of 20 min of running.

heat_per_FFT.jpg


I have since locked the FFT size to 400k and will repeat this experiment.
Code:
V24OptionsConverted=1
WGUID_version=2
StressTester=1
UsePrimenet=0
MinTortureFFT=400k
MaxTortureFFT=400k
TortureMem=0
TortureTime=3
OutputIterations=10000
ResultsFileIterations=999999999
DiskWriteTime=30
NetworkRetryTime=2
NetworkRetryTime2=70
DaysOfWork=5
DaysBetweenCheckins=1
NumBackupFiles=3
SilentVictory=0
AskedAboutMemory=1

[PrimeNet]
Debug=0
 
Last edited:
I thought NT-H1 was the one to beat as far as common and easy to use TIMs go.
That's a little short, tho, isn't it?

Look at all the work graysky put into the comparo. 52 hours sitting around waiting for the AS5 to cure! Prolly sitting there talking to himself..."the keeners at Anand will be so grateful that I just wasted 48 and half hours..." Tick-tock... "50 hours...must wait two more or the keeners on Anand will give me crap for not letting it cure... Must stay awake....if I fall asleep the curing stops..."

Anyhow, great work, graysky! Thanks for sharing. When my supersized tube of MX-2 runs dry...might take AS5 for a spin. Or NT-H1. Oh, nooooes.... ;-)
 
I believe your results. I personally use NT-H1 as it was on sale at half price of AS5. A lot of money and time was spent developing AS5, I don't believe it can simply be beaten by any ordinary thermal paste, NT-H1 included.

The only thermal products superior to AS5 are liquid metal spreads, and in theory, those diamond pastes.
 
I don't mean to be ungrateful. It's just that the epic TIM evaluation by IDC posted here on the forums put NT-H1 first among regular compounds, even over my then-favorite AS5.

Edit: Linked to thread.
 
Last edited:
I don't mean to be ungrateful. It's just that the epic TIM evaluation by IDC posted here on the forums put NT-H1 first among regular compounds, even over my then-favorite AS5.

Edit: Linked to thread.

I know...was just using your comment to launch my cheap jab at the 'curing' span that AS5 required. Which was suggested at 200 hours! Ain't nobody got time for that.

When I last used it, always got impatient...is it done yet? Is it done yet?
 
I know...was just using your comment to launch my cheap jab at the 'curing' span that AS5 required. Which was suggested at 200 hours! Ain't nobody got time for that.

When I last used it, always got impatient...is it done yet? Is it done yet?

I'm studying the cure time now with a different machine and will post the results when complete.
 
I'm studying the cure time now with a different machine and will post the results when complete.

I've always had good results with AS5. Don't forget it needs to cool completely a couple (or 5) times while curing, and really warm-up afterwards (>60C should do the trick). About 150-200 hours curing time should yield best results.
 
Consider the results I presented invalid. I did not control for the FFT size (thought I did but later realized the defaults define a range). I edited the first post of this thread and will repeat.
 
Back
Top