Taisol P4 Heatpipe (CMP411151)

Good looking but disappointing peformance – Joe

SUMMARY: Taisol make some very good heatsinks – this is not one of them.

Taisol HP

The kind folks at KD Computers were nice enough to send a sample of their latest temperature controlled heatsink, the Taisol P4 Heatpipe (CMP411151). This is certainly an impressive looking unit, with heatpipes arcing into the fins. The heatpipe attaches to the P4 with a backplate:

Base Assembly

You must remove the standard P4 retention base and replace it with the Taisol backplate – there is a rubber pad which insulates it from the motherboard.

However, the arcing heatpipes may interfere with some components on the motherboard. On the Acorp, one of the capacitors was in direct contact with a heatpipe – a very tight fit. I also noticed that the DIMM slot nearest to the socket resulted in a tight fit – it is conceivable that the heatpipes might preclude using one DIMM slot.

The fan is a Sunon #PKD1207PHV1-A – a 70 x 15mm unit rated at 38 cfm @ 4600 rpm. I found it to be tolerably quiet – I measured its noise at 62 dBA with a Radio Shack sound meter 8″ from the fan’s intake, somewhat less than a Delta 38 (about 69 dBA). It’s also safe to use a motherboard fan header (2.8 watts).

The aluminum base is well finished:

Base

Note that it is two plates bolted together. This is an important point, because the efficiency of the heatpipe depends on the transfer of heat from the baseplate to the heatpipes – more on this later.

THE TEST

I tested the Taisol P4 Heatpipe on an Acorp 4S845A motherboard with a modified P4 1500 to read CPU case temps.

TEST RESULTS – Motherboard
Motherboard

CPU Case Temp

Ambient Temp

Delta

C/W

MBM Temp

Acorp 4S845A

44.5 C

26.6 C

17.9

0.31

32 C¹

¹On-diode temp per MBM

Looking at these results, I decided to test it on the Die Simulator as well:

TEST RESULTS – CPU Simulator

Heatsink
Die Temp
Ambient Temp
Delta
C/W
Taisol P4 Heatpipe
73.8 C
24.9 C
48.9 C
0.71

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.

Results are under whelming, to say the least. Motherboard results place the Taisol P4 Heatpipe in the lowest rank of heatsinks (Heatsink Ranking) tested to date.

Curious as I am, I decided to delve into this further. I unbolted the base to see how Taisol mated the heatpipes to the base – this is what I found:

Pipes

Very little grease on the heatpipes.

Base Plate

Not a lot of grease on the baseplate.

Now I KNOW that our readers buy and use thermal grease. The OBJECTIVE is to put on enough to ensure good thermal transfer. This is NOT a good example of applying thermal grease; no doubt that performance of this heatsink was NOT helped. I would estimate that, at best, perhaps 20% of the heatpipe’s surface area contacted the baseplate.

OK, so I figure let’s add some grease and see what it can do; I cleaned off the white grease an applied a liberal layer of Cooling Flow thermal grease:

Grease

I then retested on the motherboard:

TEST RESULTS – Motherboard After Re-Greasing
Motherboard

CPU Case Temp

Ambient Temp

Delta

C/W

MBM Temp

Acorp 4S845A

39.5 C

24.3 C

15.2

0.26

29 C¹

¹On-diode temp per MBM

A marked improvement in results – almost 3 C – although it still places in the lower rank of heatsinks. I would think that a copper base might improve results somewhat – I was surprised to see it with one of aluminum.

CONCLUSIONS

As delivered, the Taisol P4 Heatpipe looks interesting but falls short on performance. Adding more thermal grease helps, but the Taisol P4 Heatpipe is not for aggressive cooling.

Thanks again to KD Computers for sending this our way.

Email Joe