CPU Cooling

Heatsink/Fan

The days of not knowing if your cooler would be sufficient for your CPU is gone. Manufacturers now make it easy to identify which heatsink works for which CPU, and with standardized thermal requirements, today’s heatsinks consistently overshoot the minimum requirements. For non-overclocked systems, the differences in CPU coolers is more about ease of installation, operating noise, reliability, and looks than it is performance. Everything changes when you need to overclock.



In the nearly two years after our last system building article, our design choice for the CPU coolers remains largely unchanged: the hybrid aluminum-copper Zalman CNPS7000B-AlCu. This design from Zalman is one of the easiest heatsinks to work with and clean and the B-spec version offers an incremental improvement over the older A version. This is due to a minimal change in the physical layout and improvement in the smoothness of the CPU-side surface. Although Zalman offers a larger 120mm cooling fan (7700 series) based cooler, the smaller unit works almost just as well without needing nearly as much space. The difference in thermal resistance is “0.22 to 0.29” for the CNPS7000B-AlCu and “0.21 to 0.28” for the bigger CNPS7700-AlCu.

By using a low-RPM, large-diameter fan with a high-surface area heatsink, noise is kept to a minimum, the hallmark of Zalman cooling designs. Our rationale for the aluminum-copper hybrid over the pure copper model is the same as it was last time – the performance benefits of pure copper are minimal, but the added weight adds unnecessary torque. The CNPS7000B-AlCu is actually within the official AMD and Intel spec.

Of course, when it comes to extreme performance overclocking, today’s best designs are still liquid cooled systems with fan-cooled radiators. Actually, according to our contacts, by the end of the decade, both Intel and AMD believe that liquid cooling may become a “standard” component in enterprise servers. That is, forced air cooling will no longer be sufficient even for stock CPUs.

Anyhow, that’s 5 years from now.

Zalman CNPS7000B AlCu
$40
http://www.zalmanusa.com/

Arctic Silver 5

Our choice of thermal grease also remains unchanged from the last article: Arctic Silver 5. Arctic Silver 5 is one of the easiest thermal greases to apply with unparalleled performance. Although there used to be concern about the silver content of the grease, today’s CPUs with large heatspreaders make the concern about the possible conductivity and capacitance a non-issue.

Arctic Silver 5 – 3.5 g (enough for ~15 large CPU cores)
$10
http://www.arcticsilver.com/

Running Total: $1000