Introduction

Since the dawn of personal computing people have found ways to push hardware further than the manufactures' specifications. Overclocking certain components made this possible, but for every action there is reaction. Overheating is what we are stuck with; always coming around to mess everything up. That is why there have been countless solutions to rid people (and their hardware) of this common problem. Nowadays it's so simple: you just have to go out and buy the best heatsink the market can provide. As for the RAM on video cards, people don't hesitate to go and buy themselves pre-made RAM sinks. In this guide however, you'll see how making your own RAM sinks can outperform any pre-made model; it only takes innovation and a skilful mind.

Parts

• Old Heatsink

• Copper Pipe

• Thermal Adhesive

• Sandpaper

Tools

• Vice (Highly recommended)

• Dremel Tool (optional)

• Metal Saw

• Heavy duty Metal file

• Sheet metal

• Hammer

Preparation

As you may know, there have been countless modification guides on making RAM sinks for video cards. Most simply recommend buying the typical aluminium heatsinks found in any modding store, but in this guide I've taken an innovative step by adding a copper base to each individual heatsink making these RAM sinks highly effective and unique. If created successfully, these heatsinks can be the most effective RAM sinks around. The copper base absorbs the heat while the thin aluminium fins dissipate it. This combination lends itself to better cooling than simply copper or aluminium alone.

If you already know the basics of thermal conductivity, you'll better understand why having a copper base is more effective. For those who don't already know, copper is second best in heat absorption. Silver takes the top of the list by a small margin, although not practical enough to replace copper due to its price. Aluminium may not beat copper in heat absorption, but it does have its own advantages. Aluminium is very cheap and easy to cut and carve, making it the most commonly used metal in heatsinks. Aluminium is also an excellent heat dissipater and some may argue that aluminium can outperform copper in some situations. By combining the best of both metals we get a heatsink with a copper bottom which absorbs heat which is dissipated via the aluminium fins.

For this project I used my own video card as the guinea pig: a MSI GeForce Ti-4200 with 128MB of RAM. (No comment on the stock GPU cooler. In the next project I plan to replace it with the best cooling around.)

Let's Get Started

Here is a typical aluminium heat sink from an old stock AMD cooler. It was a low profile cooler meant for the smaller more compact cases. I chose this heatsink because it has thin fins and a thick base. The first step is to mark the heatsink in the places you would like to cut it. Cut any unnecessary places first to avoid additional cutting later on. The measurements of the heat sink are as follows: 62mm (W), 80mm (L), and 25mm (D).

If you have a vice then you're in luck, because cutting metal is really difficult and tedious. Even using the Dremel cut-off wheels take a lot of time. So either way there isn't an easy way out, just take this process step by step. While cutting the heatsink with the hacksaw (metal cutting saw), I noticed that the metal got extremely hot and more difficult to cut. Just then I had remembered seeing a TV show about making car rims and how they cut the metal in a liquid environment. So I started pouring water on the heatsink while cutting it; it cooled the heatsink and doubled as a lubricant. It did get messy but the cutting process was cut in half, and was much easier than before.

Once you have cut all the individual heatsink pieces, you must file the sharp edges down. To make the process faster you can add water to the heatsink while smoothing it. This step isn't completely necessary, but for those who would like to present your work feel free to even lap the sides for a mirror finish. In my case I took the extra step without a second thought, because what's the point of a mod when you can't brag about its looks?

Here are the heatsinks cut and filed down. The heatsinks on the top row are going to be placed on the vertical RAM chips because their fins allow air to flow horizontally. As for the horizontal RAM chips, I created the heatsinks on the bottom row so they face in a horizontal direction as this will allow air to continue to flow in a horizontal motion.

• Plan ahead when creating your own RAM sinks; you'll want to arrange them according to your needs. Keep in mind the direction of the air flow. If you're using an air cooled GPU heatsink, it's best to have the RAM heatsink fins pointed inward.

• The way I positioned the heatsinks wasn't meant to be cooled by the GPU heatsink. They were meant to be cooler by another heatsink pushing air along both sets of heatsinks.

Now for the copper base

Get yourself the copper pipe coupler and cut it on one side. Start spreading it out, but try not to harm the surface of the copper when using tools. An easy way to flatten the copper is to bend it along a flat surface. Without using tools, you can push it along the flat surface and quickly remove the curved sides.

Next step is to make the copper completely flat. Just remember that copper is very soft; a hammer can easily dent or scratch it. To avoid damage to the copper surface, I used a piece of sheet metal along with an anvil to flatten it out. But never hammer on a rough surface; hammering softly and evenly makes the best results. Once that's done, use a straight edge to find any areas that have no yet been flattened.

Now you have to lap the surface of the copper using sand paper. I strongly recommend using coarse sand paper (150 grit) before using the fine glass sand paper. Also, cutting the pieces of copper makes your task far less troublesome. Once you use the coarse sand paper, all the high and low places on the copper will show up. Go back and hammer out those places until the entire surface is even. Once you lap the surface with 150, 400, 600, 1000 and even polishing compound, you should achieve a semi-mirror finish. Here is the unlapped surface of the copper compared to the semi-mirror surface. As you can see the lapping isn't prefect because I wanted to keep some areas rough to make the thermal adhesive bond stronger.

Now that both the aluminium heatsink and the copper plate are lapped, it's time to bond them together. There are a few important steps and tips on making the best and strongest bond between the two materials. First, you must never mix the thermal adhesive (thermal epoxy) on a paper or cardboard surface. This may be common sense, but some people do this without knowing it. If you were to mix it on paper, the fibres will mix in and weaken both the bond and the thermal conductivity. Second, the thermal adhesive is a glue and not an additional layer. You don't need a thick layer of adhesive because it will reduce the thermal conductivity between the copper and aluminium. Third, you must apply the thermal adhesive to both pieces to prevent air bubbles and an improper bond.

Then it's time to clamp them together and let the epoxy do its work. The retail Arctic Silver Adhesive says it is 5 minute epoxy, but it's more like 15 to 20 minutes. So don't rush the bonding process, simply start working on the next heatsink. If you don't have Arctic Silver Adhesive or just don't have the budget, there is another option. Using a standard thermal paste and clear 5 minute epoxy you can create your own custom made thermal adhesive. Mix 2 parts thermal paste, 1 part Epoxy A and 1 part Epoxy B. Then simply lay a very thin layer and remember that it mustn't be thick otherwise the heat will not transfer.

Notice from the last picture that there is a lot of extra copper around the base of the heatsink. This needs to be trimmed and shaved down so that the edges are flush. Here are three different heatsinks in their three different stages of completion. On the left side is the untrimmed and unlapped heatsink, in the middle is the trimmed but unlapped heatsink and finally to the right is the finished heatsink; both trimmed and lapped.

Almost Done!

Here are the finished heatsinks which are all lapped and polished. Just by touching the bottom of the heatsink I could feel the heat from my hand escaping into the metal, unlike the plain aluminium heatsink which barely took the heat off my hand. The killer combination of copper and aluminium work as a team to make the best passive coolers around.

To maximize the air flow and heat dissipation I decided to spread the fins apart using the sheet metal plate as a lever. This step is only if your heatsinks have super thin fins just like mine. Fins that are any thicker than 2mm will be almost impossible to bend as they will most likely break if they are bent any further than 45 degrees. Take caution while bending the fins because the metal is very sharp and the copper can easily be dented or scratched.

The last step before putting on the heatsinks on the RAM chips is to completely protect your hardware from any short circuits. If you take a good look at your video card, you may see that there are small electrical components which stick out almost as much as the RAM chip. In this picture they are circled with yellow rings. As you can see, they are located only a few millimetres from the RAM chips. Because the bottom of the heatsinks are copper, you need to take extra caution due to its high electrical conductivity. To be on the safe side I used small pieces of electrical tape to cover these obstructing components (as you can see from the last picture).

That's It! All you have to do now is apply the heatsinks in their designated places. For the best thermal contact, use less thermal adhesive and spread it evenly along both surfaces. Using pressure from a clamp or vice will ensure the best possible contact. (Take extra care and don't put too much pressure on your precious hardware.) Here are my results:

From the default setting of 510 RAM MHz, I was able to overclock it to 625MHz!! That's a 22% increase in RAM speed. After heavy game play using the games Halo and Savage The Battle for Newerth, I found no signs of artefacts or any other type of video glitches.

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Unique Hardware is not responsible to any damage to your software or yourself from using this guide.