At ATS we’ve long been proponents of pushing the limits of thermal management using air. Why? No one wants truly wants to use liquid cooling in their computers be they workstations, servers, telecommunication servers or any other compute engines. Plumbing is something most engineers want to avoid. So our team applauded the release of Sapphire’s passive heatsink cooled graphics card, their HD5670.
The key thing to note on this card thermally is the unique geometry of the aluminum heatsink, aluminum heatpipe and fins. Thin and compressed to their graphics card, the PCI card’s silhouette requires only one X16 lane graphics slot. Sapphire doesn’t mention recommended air flow but they do suggest for best cooling performance, a chassis installed with at least one 120mm or 90mm fan is required.
Our team thought this design was well done, and a great application for passive heatsink cooling. Some thoughts we had included:
First, the required air flow amount and air flow velocity are key for a proper thermal management solution. These will be a function of what else you have in your chassis of course, CPU, memory, disk drives etc. A key critical point is do not block the air flow to known hot components and boards in your chassis. This is a common mistake we see at ATS be it computing or telecommunications. We’ve done a write up on how to choose a fan for your computer chassis on our blog, you can read it by visiting, “Five Basic Steps When Designing for a Cooling Fan Thermal Management”
Second, whether your fans are at the air inlet or outlet makes a difference and that needs to be considered. Always mount your cooling fans on the inlet side of your electronics chassis. This allows you to direct the highest velocity airflow to the areas of greatest need. In our example here, the Sapphire graphics card and your CPU (many thanks to Tony Koryban for his wisdom on fan placement)
With creative designs like Sapphires and the correct choice and placement of fans, air cooling continues to be an excellent choice for many thermal management problems. If you need help designing such a passive heatsink approach, drop some mail to us at [email protected]
