An OK performer with a very good mounting system – Joe

SUMMARY: An OK P4 heatsink with a very good mounting system.


Size: 69 x 83 x 70 mm high; Fan: 70 x 25mm, 5700 rpm.

The good guys at SIBAK were nice enough to send a sample of their P4 copper cored heatsink, the SIBAK IC-01. This is a P4 heatsink with a 19mm copper core surrounded by aluminum fins in a radial pattern.


The copper core is finished flush with the aluminum base so that it totally covers the P4 heatspreader.

The fan is an Everflow Model #T126025DH (I think this is mislabeled; 6025 refers to a 60mm fan) – a 70 x 25mm unit that I measured at 5700 rpm; I estimate airflow at about 40 cfm. I found it somewhat noisy – I measured its noise at 67 dBA with a Radio Shack sound meter 8″ from the fan’s intake, slightly less than a Delta 38 (about 69 dBA). It draws 0.36 amps (4.3 watts) so it’s safe to use most motherboard fan headers.

The mounting mechanism is very easy to use – place the heatsink on the CPU, rotate the two levers to the closed position and that’s it. The metal arms engage the P4 retention base easily, and dismounting is also a snap – a good design.

In sum, a conventional copper core/aluminum base heatsink with a very good mounting system.


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

TEST RESULTS – Motherboard

CPU Case Temp

Ambient Temp



MBM Temp

Acorp 4S845A

42.0 C

27.5 C



35 C

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.

Motherboard results place the SIBAK in the lower rank of heatsinks (Heatsink Ranking).


The SIBAK IC-01 is an OK performer with a very good mounting system.

Thanks again to SIBAK for sending this our way.

Email Joe