Cooling System, Temperature, Overclocking

Silence is the number one priority for HTPCs. No one will be pleased to hear an incessant noise of fans while watching a favorite movie. Of course, absolute silence can only be achieved in a system that has no moving parts. It is the graphics card’s cooler that often contributes the most to the computer’s overall noise, but the Gigabyte GV-R485MC-1GI is not a solution of that kind thanks to the all-passive Multi-Core 3 Points Cooling system.

We don’t quite understand whence the name comes from, especially the multi-core allusion, as this cooler only has one heat-exchanger that has contact with the GPU die. Very dry gray thermal grease is used as a thermal interface. It looks like the additional “cores” are the small copper blocks that can be clearly seen in the photo above. These are no cheat-exchangers, though. The cooler has no additional heat transfer points, for example for power transistors or memory chips.

The heat-exchanger carries a rather large heatsink consisting of thin aluminum plates. The farthest section of the heatsink is connected to the heat-exchanger with two heat pipes. We don’t think this position optimal. One pipe should have been placed between the heat-exchanger and the side section of the heatsink for the latter to warm up uniformly. The second pair of pipes connects the cooler’s sole with an additional heatsink located near the card’s mounting bracket. Its ribs stick out through the slits in the mounting bracket by 1.5-2 centimeters. The developer must have made this to increase cooling performance but we don’t quite get the point because the cooler is passive and the heatsink gets no airflow from a fan. This solution will only work if there is high air pressure inside the system case – some of the air will be leaving the case through the heatsink, cooling it along the way. Gigabyte used a similar solution before.

The whole arrangement is secured on the PCB with four spring-loaded screws and an X-shaped plastic back-plate. The additional heatsink has no fastening and just hangs in the air on the heat pipes. The cooler is secured very firmly, without any misalignment, and the GPU die is protected against chipping with the metallic frame on its package.

For all the questionable solutions in its design, this cooler copes well enough with the card working at the default frequencies.

The GPU temperature is no higher than 86°C under load, which is the same as you can get with the reference single-slot cooler, but at zero noise. That’s a very nice result considering the core’s heat dissipation of 110W. When we tried to overclock the card, it quickly reached a GPU temperature of 101°C and the system hung up. That’s all we could achieve after a few attempts at overclocking:

This is no wonder considering the lack of a fan and that the power transistors and the memory chips are not cooled at all.

The growth of the GPU and memory frequencies is too modest, so we did not test the card in that mode. The GV-R485MC-1GI is obviously not the kind of a product that might interest an overclocker unless you add fans to it. It is not quite clear why the developer equipped it with such advanced overclocking options including software-based control over the GPU and memory voltages. This product has a special feature anyway. It is silent and supports different display devices and also offers rather high performance in games.