Overclocking and Thermal Performance

The game tests are a little disappointing. However, water-cooling isn't just about out of the box performance. It's about massively increasing the overhead for heat dissipation which usually results in bigger headroom for overclocking and much cooler running hardware too.

We used EVGA's Precision overclocking tool to see how much further we could push the clock speeds on the MSI GTX 285 HydroGen OC. In particular we wanted to boost the stream processors which MSI had left at the GTX 285's stock speed of 1,476MHz. We were also interesting in seeing how the MSI GTX 285 HydroGen OC fared against other GTX 285's in the overclocking stakes and how worthwhile spending what amounts to a significant hike in cash over an aircooled GTX 285 to water-cool it.

We managed to ramp up the core to 750MHz from 702MHz, the stream processors from 1,476MHz to 1,700MHz and the memory from 1,300MHz to massive 1,450MHz:equivalent to a riprawing 2.9GHz effective speed.

The BFG Tech GeForce GTX 285 OCX 1GB we looked at back in January managed 730MHz and 1,698MHz respectively on the core and stream processors but could only manage a 2.795GHz effective memory speed. The BFG Tech GeForce GTX 285 H2O on the other hand that we had a play with in March, reached a massive 783MHz core, 1,844MHz on the stream processors but only managed an effective memory speed of 2.816GHz. In this light, we were a little disappointed with the stream processors speed on the HydroGen, which we couldn't seem to budge above 1,700MHz without Crysis freezing even if we lowered the core and memory speeds.



The boost in Crysis from these massive hikes in clock speed was profound, no doubt due to the 244MHz increase in stream processor frequency. At 1,680 x 1,050 4xAA 16xAF the minimum frame rate jumped 10fps from a borderline playable minimum frame rate of 26fps to a silky smooth 36fps.

At 1,920 x 1,200 2xAA 16xAF, the effect wasn't quite as significant but the minimum frame rate went from a stutter ridden 22fps to a much more respectable 27fps. Either way, this kind of increase can't help but leave a smile on your face and what's more the MSI GTX 285 HydroGen OC was silent and never went above a delta T of 19°C.

Thermal Performance

We were expecting big things from the MSI GTX 285 HydroGen OC in terms of temperatures and while we've mentioned a few examples, what's really needed is a direct comparison with an aircooled GTX 285. For this we used a BFG Tech GeForce GTX 285 OCX 1GB which is pre-overclocked to similar levels.



There is no contest really, especially under load. Here the delta T is a gargantuan 37°C which is a testament to the Heatkiller water block and water-cooling in general. We really were impressed with just how capable the block is at keeping this overclocked GTX 285 in check and also while producing next to no noise. Clearly the GTX 285 is yet another graphics card that is crying out for a bit of H20.