Thermalright SP-94 Heatpipe

An excellent choice for P4 cooling, although noise preferences must be considered – Joe

SUMMARY: An excellent choice for P4 cooling, although noise preferences must be considered.


Size: 95mm x 93mm x 48mm (ex fan); Weight: 580 grams.

The good guys at Thermalright were nice enough to send one their first heatpipe heatsink to us for a test spin. This unit is available only for P4 cooling. In contrast to some heatpipes I have tested, the heatpipes are soldered to the copper base – some used thermal paste instead, with performance suffering as a result.

Parts shipped with the heatpipe include a bracket which installs on the back of the motherboard:


Assembly is fairly straightforward but does require motherboard removal. The spring-loaded bolts hold the heatsink firmly in place.

The base is well finished:


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


The Thermalright Heatpipe was tested on an Acorp 4S845A motherboard with a modified P4 1500 to read CPU case temps. For testing, I used a Delta FFB0812SHE, 68 cfm @ 4800rpm, 48.5 dBA; this features vanes in the base which straighten airflow into the heatsink. I varied rpms to give a range so users can match performance to noise tolerance.


TEST RESULTS – Motherboard

CPU Case Temp

Ambient Temp



MBM Temp

Acorp 4S845A, 4838 rpm, 70 dBA²

34.4 C

26.8 C



31 C¹

Acorp 4S845A, 3503 rpm, 62 dBA²

36.0 C

27.5 C



32 C¹

Acorp 4S845A, 3003 rpm, 58 dBA²

36.6 C

27.8 C



33 C¹

Acorp 4S845A, 2012 rpm, 52 dBA²

39.1 C

28.6 C



36 C¹

Acorp 4S845A, 1301 rpm, <50 dBA²

43.9 C

29.5 C



40 C¹

¹MBM on-die temperatures.

Die Simulator results place the Thermalright Heatpipe, at a loud 4838 rpm, in the topmost rank of P4 heatsinks tested to date (Heatsink Ranking).


Thermalright’s Heatpipe is well made and an excellent choice for P4 cooling, although noise preferences must be considered. Mating Thermalright’s Heatpipe with a variable speed fan might be the preferred approach for the power user looking for peak performance and a night’s sleep.

Note that for best performance, socket orientation must be such that the heatsink’s pipes should be either parallel to the floor or the pipes should be at the top of the socket.

Thanks again to Thermalright for sending this our way.

²Note that manufacturers measure fan noise usually 3 feet from the fan.

Email Joe