As summer approached, I became concerned about the high temperatures of my video card, a Gigabyte GV-RX80L256V
with its stock passive cooler ducted to the motherboard fan. When running ATI Tool, the GPU temperature would climb above 120*C in about 10 minutes. Not good.
On a lark, I thought I would try an Aerocool VM-101
cooler after reading a review that extolled its cooling ability.
At first I tried installing it upside down (below the video card), hoping that the heat pipes would loop around the TV card, and I could use a shared duct to exhaust the heat from both cards. Unfortunately, the heat transfer block sticks out too far below the video card and intrudes into the PCI slot that the TV card was supposed to go in. Bummer.
So I installed it the way it's intended: with the fins on the solder side of the video card. Mounted this way, it hangs out over the north bridge, so it is incompatible with an HR-05. Here is a photo of it installed:
As seen above, this cooler is huge
, and spills into the slot below and at least two slots above the PCI-E slot it's installed in. However, its cooling is outstanding. My GPU temperatures dropped into the low 80s running ATI Tool with no change to the air flow.
Since I still wanted to evacuate the video card heat directly, I had to construct a new duct. I opted for a very simple duct consisting of two flat styrene panels. The other two sides of the duct are provided by the motherboard and video card PCBs. Here's a photo of the duct outside the system:
and inside the system:
The two diagonal bits on the outside of the duct divert air from the motherboard fan (visible at the right edge of the last photo) onto the north bridge heat sink.
This ducting arrangement worked well, pushing the GPU heat directly out the back of the case via an open PCI slot. It also had the unexpected side effect of dropping the reported motherboard temperature by 3 degrees, and raising
the reported CPU temperature by 3 degrees.
The motherboard temperature change is fairly easy to understand since the airflow paths around the new video duct are simpler and smoother than around the old one. The CPU temperature change is a mystery, since the CPU fan is getting its air from a completely separate path from the motherboard fan. I compensated for this temperature shift by swapping the CPU and motherboard fan voltages, so now the CPU fan runs at 805 RPM and the motherboard fan runs at 770 RPM.
The system remains as quiet as before, but now the GPU is over 30*C cooler under load.
A couple of notes about the VM-101. As pointed out above, it is big
: unnecessarily so. The screws that clamp the heat pipes to the heat block stick into the next PCI slot about 2mm, and the fins are so far above the back of the card that they intrude into a second PCI slot by a few mm or into the north bridge space, depending on what slot is used.
Also, when first installed, the heat block slides around on the GPU. This is easy to fix: wait a day for the rubber grommets to compress a bit, then retighten the nuts on the back of the card.