NVIDIA’s Focus upon Acoustics and Heat

One of the main critiques leveled against the GF100-based cards was their rampant heat production leading to high fan speeds. Using a GTX 480 in particular was never what we would call a completely silent experience but many of the critiques were blown a bit out of proportion in our opinion. Nonetheless, NVIDIA went back to the drawing board in order to completely redesign their high-end cooling solutions in order to focus upon lowering heat and shrinking the acoustical profile of their flagship products.The first step was to discard the inefficient and massive heatpipe setup which came with the GTX 480. The replacement is a vapor-chamber cooler that quickly whisks away heat from the core in order to distribute it evenly across a large aluminum fin array.A vapor chamber design is broken into a number of components. There is a copper base-plate that makes direct contact with the core so the water contained therein will quickly vaporize on the evaporator and make its way through the chamber to the condenser. The condenser wick is placed up against the upper cover in order to disperse the heat generated as the hot water vapor condenses. Finally, there is a transportation wick for liquid return that is used to move the condensed water back to the vaporization wick. Think of this like a massive flat heatpipe which is infinitely more efficient at dispersing heat over a large surface area.In order for this method to be effective, the entire chamber needs to be sealed and put under vacuum. This is due to the fact that water vaporizes much easier in an environment with extremely low air pressure. Thus, it is very important that a vapor chamber cooler is well made without any manufacturing defects or the air pressure within the vapor chamber will decrease and this will result in lowered heat dissipation capabilities.Other than the custom vapor chamber, there are additional features packed into the GTX 580 what are used to lower its overall noise profile.Through testing, NVIDIA found the GTX 480’s fan had blades that were vibrating slightly which created certain tonal characteristics that could be annoying to some people. To rectify this, a tension ring was added around the fan’s edge and hub’s bottom was filled in to reduce friction. The whole setup was then placed closer to the fin array to allow the fan to spin at lower speeds when pushing cool air into the heatsink. For SLI systems, a small indent was added shroud’s rearmost portion which should allow for slightly better airflow.The result of all these changes is of course a temperature reduction but additional benefits have been reaped in the acoustical department as well. According to NVIDIA, the GTX 580 should be quieter than a GTX 285 without any sacrifices in the thermal department due to “new” adaptive fan control. Basically, this mean the fan will ramp up in a much more linear fashion rather than the sudden jumps we saw with the GTX 480. Since it adjusts fan speed in real time based on core temperature it never really needs to run at high speeds since temperatures are kept in check from the get-go.Most ultra high end cards exhibit absolutely epic power consumption numbers and the GF100 was no different. However, in order to better manage voltage fluctuations and power spikes, NVIDIA has implemented support for real-time monitoring of 12V voltage readings. If the reading on any of the PSU’s rails drops or increases by a set amount, the VRM modules on the card will immediately compensate. This should not only lower overall power consumption but also protect the card against “dirty” power from cheap PSUs.In addition, the hardware monitoring modules are able to work hand in hand with the GF110 core to dynamically adjust performance to keep consumption within NVIDIA’s specifications. Overclocking won’t be affected by this unless you want to push things to obscene limits with exotic cooling but power “viruses” like Furmark which stress the GPU beyond its design limits will see their effectiveness reduced.