Cooling System Design
So, the GV-NX76T256D-RH is equipped with an original passive cooler called Silent Pipe II which deserves a separate section in this review. There are no special innovations in this cooler; it uses the time-tested heat pipe technology, yet its design is very original, at least we haven’t yet met a solution like that in our practice.
The GPU die has contact with a small copper heatsink two heat pipes are pressed into. Each pipe is connected to its own heat-spreading section. The first section consists of 20 aluminum ribs and is located on the GPU side of the card. It is installed on a double-height mounting bracket and the rounded ends of the ribs go outside the bracket, i.e. outside the PC case. This is meant to improve the efficiency of the cooler by means of natural convection (the heatsink is passive, i.e. no fan is blowing at it), but the protruding part isn’t longer than 1-1.5cm and is unlikely to have a big effect on the cooler’s performance. Moreover, this placement of the front heatsink makes the card a dual-slot device, which may prove inconvenient for small system cases or barebone systems.
The second heat-dissipating section is installed on the reverse side of the PCB and consists of a copper base and thin aluminum plates. The bracket under the heatsink serves as a limiter that prevents the heat pipe the heatsink is fastened to from unbending and breaking. Since this is its only fastening, the heatsink actually hangs in the air and can move to and fro in the range defined by the limiters on the bracket. This section is the main heat-dissipating element of the Silent Pipe II cooler. It is placed at the reverse side of the PCB and, in a tower system case, will turn to be on top after installation which will improve heat transfer due to convection: the hot air from this heatsink will be rising up to be replaced with cooler one. An intake fan at the bottom of the system case would help the process. The heatsink ribs are positioned perpendicularly to the side panel of the PC case, so any system fans on this panel will help improve the cooling of the Gigabyte GV-NX76T256D-RH, too.
The Silent Pipe II cooler developed by Gigabyte looks a well-thought-out and effective solution that has only one significant drawback. It is rather big and may not fit into a small system case. This cooler should cope well with cooling a G73 chip, but you may want to provide additional air cooling to increase stability, especially at overclocking. The memory chips are not cooled at all, but GDDR3 chips in modern 136-pin packages are stable at frequencies up to 700 (1400) MHz without enforced cooling. Of course, you should take care about memory if you are overclocking your Gigabyte GV-NX76T256D-RH, not only to protect it from damage but also to reach higher frequencies.