In fact 1GHz benchmarkable is not a problem! That's more than a 50% overclock from the default 650MHz! However, the memory on the card is not as overclockable. I've had trouble trying to hit 1GHz on the memory, the memory would get unstable all of a sudden and crash the system, even when there no visual artifacts on screen. First thing I've tried was to increase Memory voltage which did not help at all. Next I tried soldering some SMD capacitors to see if it helps but that didn't work as well. Next, I decided to try cooling the memory better. RAMsinks are usually used for this purpose, but I was looking for something more cooling... a lot more cooling. I could throw some Dryice on the memory but that would entail the hassle of ordering dry ice everytime I want to do some benchmarking. So I decided to try out something extreme, using refrigeration phase change on the graphics card memory!
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