:: PCSynapse :: Arctic Silver 5 High-Density Thermal Compound

With the dawn of high performance processors, cooling demands have vastly increased. Modern microprocessors need to be adequately cooled, or they face performance problems and a gradual loss of stability. While heatsinks and waterblocks are what many consider the essence of a computer cooling system, an equally important yet often overlooked component of a satisfactory cooling system is thermal interface material. Thermal interface material fills in the microscopic pores between the processor and heatsink. Without thermal interface material, performance and reliability suffer. While thermal interface material can come in many different varieties – such as pads, epoxies, and pastes – the most common and effective is thermal grease. One of the most effective thermal compounds out today comes fresh off the lines at Arctic Silver Corporation - Arctic Silver 5.

Arctic Silver 5 is one of the latest, most advanced, and best performing thermal greases available on the market. Sold in 3.5 or 12-gram packages, Arctic Silver 5 can be used on five to 40 processors, depending on the size of the processor and the amount you purchase. The compound consists of 3 different silver molecules, sub-micron zinc oxide, aluminum oxide, and boron nitrate particles suspended in polysynthetic oils. The particles increase thermal performance and long- term stability of processors. The compound is designed for easy application from the tube, and increased performance after application. During the first few thermal cycles – the process of compound heating and cooling – Arctic Silver 5 will thin out over the processor and heatsink, filling in microscopic valleys and eliminating imperfections. After the compound has thinned, it will thicken until it reaches a final consistency after 50 to 200 hours. Once Arctic Silver 5 has arrived at its final consistency, the drop in temperature is quite noticeable; often two to ten degrees Celsius. This drop in temperature will yield better overclocks and improve system stability and longevity.

(Above-Left): Arctic Silver 5 Syringe / (Above-Right): Arctic Silver 5 w/Sterile Prep Pads for CPU Cleaning
(Click To Enlarge)

You will notice the qualities of Arctic Silver 5 as soon as you pick up the tube. I was surprised by how heavy the 3.5gram tube was, and this can only be a result of the high density of Arctic Silver 5. Application of Arctic Silver 5 was extremely easy, and the texture of the Arctic Silver 5 from the tube is an added aid in application. The compound requires some force to move out of the tube, and is somewhat thick upon application. This ensures you don’t apply too much thermal grease, which would mean cleaning the processor and heatsink again, and also causing a good amount of the compound to be wasted.

As the latest thermal compound by Arctic Silver, Arctic Silver 5 is said to outperform every other thermal paste on the market. It has been painstakingly reformulated by the folks at Arctic Silver to be the new reference for thermal compounds. As opposed to the now discontinued Arctic Silver 3's 75% silver content by weight, the new Arctic Silver 5 contains over 80% by weight of thermally conductive material. When compared to Arctic Silver's Ceramique compound, Arctic Silver 5's advantages are apparent. While Arctic Silver Ceramique shares exclusive features like "Controlled Triple-Phase Viscosity", "Pure Electric Insulation", and "High Density"; Arctic Silver 5 contains 3 different sized and shaped 99.9% pure silver particles, which amount to superior cooling properties. Arctic Silver estimates that users of Arctic Silver 5 will experience a loss of 3-12 degrees Celsius, as opposed to Arctic Silver Ceramique's 2-10 degree loss.

To test Arctic Silver 5’s real world performance, I chose to measure temperatures of my CPU with both the stock thermal grease and with the Arctic Silver 5. Both tests occurred on the same computer running a generic aluminum heatsink with a 60mm fan. All temperatures are CPU die temperatures. Idle temperatures were measured through the BIOS hardware monitor after letting the system stay in the BIOS for 10 minutes. Load temperatures were measured with Motherboard Monitor 5 while CPU Burn In v.1.1 ran a stress test without error checking to maximize the CPU temperatures. Immediately after application of AS5, my temperatures on the CPU dropped about 6 degrees Celsius while idle, and 3 degrees under 100% load. Considering that my stock thermal grease was only able to achieve 46 degrees idle and 65 degrees load. Arctic Silver 5 made quite an improvement over my temperatures, even though I applied it merely 5 minutes before. Arctic Silver 5, like many other thermal types of grease, has a “break-in” period, where the thermal compound changes consistency, fills in the imperfections, and increases in performance. To accelerate the “break-in” process, I ran CPU Burn In v.1.1 for 10 minutes, then let the heatsink cool to room temperature, and then repeated. After a few thermal cycles my temperatures did not improve, signifying the end of the break-in period. Once the break-in period is complete, the computer does not need to be turned off, and the idle and load temperatures will not change much between thermal cycles if at all.

(Above-Left) Stock Thermal Paste vs Arctic Silver 5 / (Above-Right) Arctic Silver 5 Initial vs Final Temperatures
Click pictures to enlarge

During the break-in period, Arctic Silver 5 drastically increased in performance. After my initial temperature drops, Arctic Silver 5 lowered my temperatures even more. My idle temperatures were in the 30 degree Celsius range, and load temperatures were now between the upper 40s to mid 50s. Overall, my temperatures dropped about 15%. You may have more or less luck, but expect at least a 2 degree Celsius drop. Dropping about 15 degrees Celsius on the CPU is a great achievement, and will greatly help any overclock and increase system stability.

Above: (Left) Thoroughly cleaned CPU / (Right) Arctic Silver 5 applied to CPU right before heatsink installation

If you are in the market for thermal grease, Arctic Silver 5 is a great choice. At around $8 USD for a 3.5gram tube and around $20 USD for a 12gram tube, they’ll make great inexpensive gifts for any computer enthusiast this holiday season. If you need increased stability, higher overclocks, or just lower temperatures for bragging rights, Arctic Silver 5 is a solid choice.

Many thanks to Arctic Silver for sponsoring this review.