MSI GTX 285 HydroGen OC Review

The Heatkiller GPU-X² water block

Something that bothered us with the GTX 280 HydroGen OC was the fact both barbs have to face the same way. Unfortunately the same is true of the MSI GTX 285 HydroGen OC. A black acetal port mount is secured to the block by means of two hex screws. This can be removed and inverted so at least your not stuck with having your barbs facing in just one direction (up is default).

Inverting the port mount is relatively easy. The only thing you have to watch is the rubber o-ring that sits between the block and the mount providing a seal. Even so, plumbing in two or more cards like this would quickly prove to be a bit of a nightmare and would look pretty ugly too.

If you're planning an SLI system though, you have two options. Water-cool offer a 4-way adapter for the Heatkiller GPU-X² water block which replaces the stock port mount with one with two ports on the top and bottom with a similar configuration to other water blocks. They also offer adapters than can link two or three blocks.The other option is to opt for a Dangerden or EK full cover waterblock which usually have four ports as standard.

The block itself is a work of art and typical of German engineering. It's slimmer than other blocks we've seen and it hugs the PCB from front to back, neatly slotting itself between capacitors and easing in between other parts of the VRM circuitry, at the end of the PCB (Ed: That was somewhat erotic, Antony!).

There are a total of sixteen mounting screws securing the block to the PCB on the topside, and as all the RAM chips are located on same side of PCB, you don't have to worry about adding extra ramsinks - something that was a good idea when water-cooling the GTX 280 as the RAM can get pretty darn hot when left to its own devices.


Unlike other blocks we''ve seen, Heatkiller full cover blocks are made up of three main copper parts which fix firmly together. We couldn't help but take a peek inside and what we saw was a very different design to the likes of Dangerden and EK Waterblocks. On the other side of the narrow inlet and outlet are two channels separated by a bridge of copper. On the contact plate are a series of extremely fine channels through which the coolant is forced, each being less than half a millimetre wide.


We haven't seen channels this fine since the XSPC Edge CPU block, and that was discontinued due to the fact that making fins this small is so difficult. We're not quite sure what the black residue is but as it's only located inbetween the copper plates, it's most likely some form of thermal paste.


As we've already mentioned, the Heatkiller has a higher impingement than other blocks we've seen. The inlet and outlet ports in particular are very slim indeed which can only lead to higher pressure inside the block and in theory better performance. This is certainly what we saw when comparing the BFG GeForce GTX 280 H₂OC and the MSI GTX 280 HydroGen OC, with the latter managing noticeably lower temperatures.

The downside to this is that the Heatkiller block isn't as well suited to loops with a significant amount of hardware, with EK and Dangerden blocks offering lower impingement. However with modern powerful pumps such as the Laing D5 or DDC-1T Ultra, the difference will be negligible in most situations.


There's also next to no room between the barbs once you've thrown some 1/2"ID tubing on, so jubilee clips only just fit, but there's a fair it of wriggling required. This also meant that straight 1/2" compression fittings didn't fit either although we found that Feser 45 degree rotary fittings do fit following a little persuasion.