Homemade Thermal Grease

Ever had one of those days where you reach for your tube of Arctic Silver, and realize there’s nothing there? Yeah, haven’t we all. Here’s a quick guide on homemade thermal grease from items you already have at home.

A few months ago, I was stuck in such a situation. Upon realizing that I had cleaned all of the Arctic Silver 5 off of my CPU, not knowing I was completely out of it, I began to look for an alternative… rather than coming up with my own grease at first, I googled alternatives.

I found Dan’s Data Thermal Grease Comparison, which included some standard fare thermal
greases as well as a few odd ones (toothpaste being the prime candidate here). Reading that article, you’ll notice how well toothpaste transfers heat.. better than Arctic Silver 3! There was one problem, however – toothpaste tends to dry out. Bummer! Not to be outdone, I began searching the bathroom and came along this little jewel:

Vaseline

Thus begins our first experiment – toothpaste for conductivity and a small amount of Vaseline or a similar petroleum jelly product
to keep the toothpaste from drying (75% toothpaste and 25% Vaseline was the best in my testing, mix well). I used standard Colgate toothpaste here. When choosing a toothpaste, look for brands without grit – that will hinder heat transfer
considerably. Well, the results of this combination, were very surprising, to say the least!

The combination, in all of its Ghetto Glory:

Keep in mind that the fluoride in toothpaste can be slightly corrosive, and as such shouldn’t be used in your rig 24/7, especially on exposed die CPUs, such as AMD’s Athlon XP (Socket A) or Intel’s Pentium III (Socket 370). I will not be held responsible for your use of this article and any problems you may encounter!

Diaper Rash Cream

In our second experiment, most people would consider pure foolishness – diaper rash cream.

Looking at its ingredients, Desitin brand diaper rash cream¹ contains 70% Zinc Oxide and a lubricant. This combination stays liquid at all times – no need for vaseline. The good thing here is that Zinc Oxide is the main ingredient in white goop thermal greases. White goop compounds usually have ~30-40% Zinc Oxide with the rest being the filler material, usually silicone. Again, the results are very surprising, in a good way.

Notice I tried to fancy it up by putting it in a syringe ;).

Now that we’re through all of that, on to the results!

The Test Bed:

• Pentium 4 3.2c @ 3.73 GHz, @ 1.7 volts
• Cooler Master Jet 4 HSF – Full Speed

Ambient temp was roughly 23ºC for these tests, running Prime 95 for five hours:

• Arctic Silver 5, fully burned in 43~45ºC
• Toothpaste + Vaseline: 46~49ºC
• Desitin Diaper Rash Cream: 46~48ºC

Wow, those results speak for themselves! Toothpaste + Vaseline and Diaper rash cream are almost equal. Choosing between the two, diaper rash cream is the obvious choice,
given the fact that it doesn’t have the corrosive properties of toothpaste and I noticed very slightly lower temperatures with it.

Again, I must stress, this isn’t a permanent solution. Go buy some thermal grease when you have the chance – this is only a temporary solution.

I hope this helped some of you out there with no other avenue – I know it helped me!

¹Funny, I don’t even have any babies in my house… why I have Desitin, I’ll never know.

Jeremy Johnson