draft0 - a shared blog by just some people

In this entry I'll describe how Fred's components are air cooled.

So, after removing the fan wall and unplugging the two fans in the back of the case there was no active cooling left. That's good for reducing noise, but not enough cooling for the hard drives, the CPU and the SAS controller cards. Since the case is not mounted in a rack and nothing is placed on top of it, I decided to use the space in the case lid to place larger fans.

The CPU

My idea was to replace the CPU cooler with a larger one that just fits into the case and have a fan above it suck out its hot air (also pulling in ait from the RAM modules next to the CPU socket). I fount a heat sink from Scythe called Iori (SCIOR-1000). Mounted on the socket there would be just enough space for a 15 mm fan above it. As it turns out though, the heat sink is large enough to cool the CPU passively and the RAM doesn't need any additional cooling, too. So the fan above it is not even plugged in.

The Extension Cards

Since the HBA and the RAID card that I'm using are designed for servers with a proper airflow, they need at least some additional cooling. Their heat sinks are quite small for the amount of heat they produce. But there was enough room above them to place a fan that sucks the hot ait directly from the extension card area out of the case. I was told these cards usually don't have any problems getting extremely hot. But I rather don't want to have them do their things for hours or days streight without any active cooling. Replacing their heat sinks with larger ones would only be a sufficiant option if there was room for much much larger heat sinks.

The Hard Drives

I don't want to have have hard drives run continuesly without any active cooling, especially when they are sitting in enclosures that don't allow for any aitflow without some amount of pressure. There is just no-where for the heat to go on its own in these tight drawers. I decided for three 140 mm fans that would neatly in a row behind the hard drive compartment and backplane. Since the motherboard isn't that large, there was nothing but a few cables in that area of the case. I've mounted an aluminium bar that I had lying around and tucked two pieces of flat plastic between this bar and the bar that originally held the fan wall at the bottom. That way, the air that is pressed in from above gets directed only into the hard drive compartment where it has no way to escape without passing the hard drives.

Unfortunately the room around the hard drives is so small that quite a lot of air preassure is needed to cool them as much as I wanted to. Running the fans at full speed all the time is hardly enough to keep them at a temperature that I deem acceptable. I tried to increase the cooling effect by sealing all the edges and other tiny spaces where some air could escape without cooling the hard drives. But this didn't lead to a measurable difference. I ended up taking out two of the 16 hard drives to increase the size of the duct. I chose two drives in the centre so that there now is a large surface where the air cools the remaining drives. That lowered the temperatures of the surrounding drives a lot. The temperature of the drives at the edges was of course hardly effected. But those weren't the problem anyway.

I'll probably continue about the rest of the case mod in a followup entry.