The second heat sink + fan that I ordered is now on its way to the house. This is a result of Episode 182, a tragic accident involving a spinning fan and an errant thumb. I had quite a time finding the first heat sink + fan, as I wrote in Open Comments Friday at the TechBlog:

My problem is that my CPUs are Xeons, socket 604. The motherboard is one that Asus classifies as a server mobo. In other words, it’s not your typical Pentium 4 box. I’m a corner case. An anomaly. An oddball.

That holds true not just for Fry’s but for many of the PC components shops in the Internet and for the people making heat sink/fan combos. (I only needed a fan, but you can’t buy a fan without a heat sink unless it’s one of the standard fan sizes, which my Intel CPU fan ain’t.) Finding a suitable fan for my socket 604 CPU was hard.

The first problem is that the socket 603/604 CPUs use a mounting system where the heat sink bolts through holes in the motherboard to the CPU tray. Some heat sink makers take their P4 heat sinks, add a cheesy looking plastic adapter, and call it a socket 604 heat sink. This arrangement might work, and it might be effective, but I believe I’m better off with a heat sink that bolts on directly, so I eliminated these heat sinks.

The next problem is that you can’t trust some resellers out there. More than once I found a heat sink advertised as being for “socket 603/604″, but when I went to the manufacturer’s web site to check out the specs directly, the manufacturer did not claim 604 compatibility. In one case, the manufacturer said “603 only NOT FOR SOCKET 604!”. I don’t know what the differences are, because the 603 and 604 mounting systems look the same. Perhaps the difference is due to an increased heat output with the 604?

Another problem is that, because the Xeon is generally considered a server CPU, and servers are often rack-mount machines, many of the heat sinks were designed for 1U installations - in other words, very short. For example, I found a nice looking heatsink/fan from Vantec, and this is probably the one I’d have ended up with, except I really wanted one with a bigger heat sink. Bigger heat sinks have longer fins, which means more surface area to radiate heat from. That means you can move more heat away with less airflow, thus lower fan speed and less noise. (It was noise, a rattling CPU fan, that got me started down this path in the first place.)

So finally, while researching one heat sink, I found another, this time the right one. The Thermaltake A1964 is a 2U heat sink, meaning that it’s designed for server rack-mount installations, but in double-high boxes. In other words, it’s got radiating fins the same length as the heat sink that Intel delivered with my Xeon CPUs. It’s not real pretty with that aluminum mounting bracket hiding the pretty copper heat sink, but I don’t have a window in the side of my case, so I guess I don’t care. The deal clincher: the A1964 bears “recommended by” certifications by both Intel and Asus.

The best part about finding this heat sink was when I finally installed it. It’s quiet! I gave it a one-to-one listen test against the (one still functional) Intel CPU fan, with all the other fans and disk drives in my box disconnected. At full speed, around 5200 RPM, both the Thermaltake and Intel fans are noisy, but the Thermaltake makes only about 80 to 90% of the noise of the Intel fan (I’m guessing at that number, because my ears are not well calibrated). More importantly, at that speed, the Thermaltake’s noise spectrum clearly has fewer high-frequency components in it. In other words, it doesn’t make the annoying WHINE that my Intel fan does.

Even better: at low speed, around 3000 RPM, where my fans run most of the time thanks to Asus’s Q-Fan feature, the Termaltake is nearly silent, much quieter than the Intel fan. I’d guess it makes only about 5% of the noise of the Intel fan at low RPM. This is a HUGE win. I’m going to order a second Thermaltake fan for my other CPU… I’m not going to wait for the day I stick a finger in its fan.

I wrote about that at TechBlog rather than here because when I write about my computers here, it causes Leigh Ann to write comments that say things like “YAWN”, and because it causes Jackie to tell me, in person, how boring my blog has suddenly become.

However, I’m writing today because I’m truly excited about getting this second fan. If you understood how much noise my system used to make, you’d understand. My system will still be noisy when it’s working hard, but in more typical situations like reading email, browsing the net, or editing videos, it should now be whisper quite.

This entry was posted on Friday, March 10th, 2006 at 5:18 am and is filed under PGDC. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.