Thermalright SLK700

Excellent balance between noise and performance – Joe

SUMMARY: Outstanding performance at tolerable noise levels.


A while ago we took a look at the Thermalright SLK600 and the Thermalright SLK800.

Now rounding out the family is the SLK700 – the good guys at Thermalright were nice enough to send one for a test spin.

The SLK700 ships with YS Tech’s
TMD fan (PD1270155B-2F) – a 70 x 25mm TMD unit (small fan hub – drive magnets in fan perimeter) – rated at 36 cfm @ 5600 rpm, 38 dBA¹. I found it to be tolerably quiet – I measured its noise at 61 dBA with a Radio Shack sound meter 8″ from the fan’s intake, substantially less than a Delta 38 (about 69 dBA). It’s also safe to use a motherboard fan header – 3.8 watts.

The base is well finished:


When I ran my nail over it, I could not feel or hear any ridges.

In summary, typical Thermalright quality and finish.


The SLK700 was first tested on the CPU Die Simulator which gives results that are unaffected by motherboard influences. I then tested it on an Shuttle AK31, modified to read AMD’s on-die diode, as an example of what users might see on their systems.


Die Temp
Ambient Temp
SLK700/YS Tech TMD, 5254 rpm
40.2 C
20.0 C
20.2 C

TEST RESULTS – Motherboard

CPU Die Temp

Ambient Temp



CPU Back Temp

XP @ 1467, Shuttle AK31

38.5 C

21.1 C



32¹ C

¹In-socket thermistor per MBM

Delta = CPU temp – Ambient Temp
C/W = Delta / CPU Watts

Interpreting C/W: For every watt (CPUw) that the CPU
consumes, the HSF will limit the CPU’s temperature rise to (C/W x CPUw)
plus the temperature at the HSF’s fan inlet. For example, at an ambient temp of 25 C, a C/W of 0.25 with a CPU radiating 50 watts means that CPU temp will increase 50 x 0.25 = 12.5 C over ambient temp, or 37.5 C. The lower the C/W, the better.

Die Simulator results place the SLK700 in the top rank of heatsinks tested to date (Heatsink Ranking).


Thermalright’s SLK700 is a fine choice for Socket A cooling. With YS Tech’s TMD fan, noise was tolerable; considering cooling performance, the SLK700/TMD combo is an excellent tradeoff between noise and performance.

¹Note that manufacturers measure fan noise usually 3 feet from the fan.

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