About us

Scan Windows 7

A chip saver?
Product : DTS-400 Copper Shim for Tbird/Duron
#Price : ~ 7.00
Available from : CPUFx
Related articles : [Alpha PAL6035]- [Coolermaster Heatpipe]
Discuss this review in our forums

Copper shims have become a necessity after the early stories of Thunderbird & Duron cores being cracked by heatsinks putting too much pressure on the core of the processor. These shims allowed the heatsink to spread the pressure over a greater surface area, and anyone that has done elementary physics will know that pressure is equal to the force divided by the area. So if the force remains the same, but the area is increased, then the overall pressure on any one point will be less.

The first shims on the market weren't very well made and were the sort of standard you would expect from a home-made garage job, however production techniques have been refined and we now look at one of the best shims available on the market, the DTS-400.

Logically the shims are made out of copper, because of it's good heat conductivity. However any metal which is only a few millimeters thick is quite easy to bend, therefore CPUFx have decided to make it a copper alloy.

We got more than one in for review which let us have a look at how the quality is in general, rather than just a one-off review piece. Frankly, we were stunned when we saw the quality and the level of engineering that went into these copper shims. We were expecting rough edges left by drill holes and non uniform edges, and none of these defects were present in all of the DTS-400s.

CPUFx say they press each DTS-400 twice for uniformity, and this certainly seems to be true. Each shim is very smooth on both sides and has no bumps. Obviously if you inspect it under a microscope then you might see something, but then again we can talk about metal molecules and be here forever.


Installing the DTS-400 is very easy, and you require very little other than the heatsink you are placing on the processor. No epoxy is required to hold the DTS-400 in place, because once the heatsink is over it and held in place by it's retainers then the DTS-400 won't fall out or slip.

You will have noticed that we mentioned how smooth the surface of the shim was, and this is very important when looking at the heat transfer and how well the shim fits between the heatsink and the processor. Air gaps is the worst thing you could want when you are thinking of heat conductivity.

Results We can't test the copper shim like a heatsink, but we tried to see if there was any temperature difference when using the copper shim and when not using it. We saw little variations. The heatsink /fan we used in these tests was the Alpha PAL6035 (reviewed here). The Thunderbird CPU was not overclocked, and therefore ran at the factory set, 800MHz.

So we see there is very little difference in temperatures, but we have to think back to the reason why these shims were made. They were produced to save the user from breaking the processor when applying a new heatsink. The DTS-400 certainly manages to do that task well, and as an added bonus you get a slight decrease in processor temperatures.


The copper shim isn't designed to improve the thermal performance and only has minimal gains in that area, however the shim does provide the security (not certainty - we might hasten to add) against cracking your Thunderbird/Duron processor. The workmanship that has gone into these shims are faultless, and their finishing is of a very high standard.

If you are a Thunderbird/Duron owner then we recommend you get the shim.