Applying Thermal Compound

[nheather]

In the past I have applied AS-5 using a razor blade to spread it thinly over the Processing Unit and then apply the heatink with a little twising back and forth to make sure it is bedded in.

I will soon have some more CPUs and GPUs to do and have bought some MX-3.

From what I have read the favoured approach nowdays is to apply a blob in the centre and then squish and twist it with the heatsink.

Whilst I understand some of the benefits of this approach I'm a little concerned how you know whether it has worked - covered properly.

For example, if you put a blob in the centre of a large square CPU and you squish it down, won't it naturally form a circle - if so either some of the chip will not have thermal compound or you will have compound squidging out.

What method do you use?

Cheers,

Nigel

 

[nheather]

I used the 'Line' method from the Arctic Silver website.
http://www.arcticsilver.com/arctic_s...structions.htm
I have good temps, 44-79 on a warm day.

Thanks for that link - there are no instructions for MX-3 and MX-2 just use the blob approach.

Interestingly, the instructions (above) for Intel say to use the line method and for AMD the centre blob method.

The instructions also state that this doesn't result in full coverage between the CPU metal surface and the heatsink, just the area where the cores are located.

I'm sure that will work, but I must admit, I'll feel more comfortable with the complete surface of the CPU heatspreader covered, so I'll probably stick to my old method - after all the CPUT retail sinks have thermal compound over the complete heatsink surface not just the area that will cover the cores.

The AS-5 instructions also only cover CPUs so a full spread might be safer for GPUs and other processors.

Cheers,

Nigel

 

[nheather]

I have just fitted a GPU heatsink armed with this advice and in the end reverted to my tried and tested method.

The reason is that the heatsink as 4 threaded parts which protrude through the PCB so you can't twist the heatsink so I was a little worried about coverage using the 'centre pea' method.

So out came the razor blade to spread the thermal compound around and found that MX-3 doesn't spread very well at all - looks like the 'centre pea' approach is essential with MX-3.

So I reverted back to Arctic Silver 5 which by comparision spreads like a dream.

Cheers,

Nigel