The G750JH Customized GTX 780M Graphics Card And Cooling

Sep 10, 2013 Written by:ROG Article

The G750JH is more than just a G750 with a new GTX 780M swapped inside; the ROG engineers had to make significant customizations in the chassis, cooling and even down to the core graphics PCB itself! Let's start with the the reason why most are interested in the G750JH: the new GTX 780M. [gallery include="" size="medium" link="file" template="file-gallery" columns="2"] This is not a standard GTX 780M, the PCB is redesigned by ASUS engineers to be significantly bigger, which affords more components and more space between them too. Together this improves the provision of power, reduces EMI and the extra space aids cooling. In all, this GTX 780M is more tolerant and reliable. It's 3-phase power design (the entire PCB to the right of the memory chips) consists of 2-up, 2-down MOSFETs and upgraded, high-performance Tantalum capacitors. The 4GB of memory is supplied by 16 5GHz GDDR5 chips split between back and front sides, with the 1536-core'd GTX 780M in the middle. All that power needs to be cooled, and as you'd expect, this beast runs hotter than the lesser graphics cards, so needs extra cooling. Firstly let's look at the heat-plate that covers the entire PCB: GTX780M-heatsink-1 As you can see below, everything significant is cooled to ensure it runs smoothly. As with all G750 [and older G5s, and G4s etc] the graphics card is cooled separately to the CPU. With two heatpipes directly to the GPU core and another dedicated to the power hardware, no area is left out and it can quickly draw away heat to the fan. And yes, even the heatsinks are ROG branded!

At the other end of the heatpipe the fans and heatsinks are sufficiently upsized to cool it all. The example below is for CPU and GPU; the thicker fan and heatsink are the same for both, exhausting at either side of the rear of the G750. [gallery include="" size="medium" link="file" template="file-gallery" columns="2"] The double-size heatsink is cut to match the chassis size exactly, which means the chassis enlargement has been minimized to keep its profile and weight as slim as possible.