Summary This is my latest Cube mod and most challenging. It started out as "I wonder if a Cube can be water cooled?" and grew by stages into what you see here as a final result. Some might say that it has been modded so much that it is no longer a Cube. I stick by it though as to me it has all the essential Cube elements of acrylic outer case, cool touch sensor, re-uses most of the internal structural parts. Gone though is the large passive heatsink (no point in a water cooled set up) and the handle mechanism - there was just no room! The Cube is cut down and lies on the side just because (a) the case came initially from an old mod that I did for my wife to hold her old Mac Mini in and ( B) the mod has a practical purpose living under my TV, so a cut down arrangement on the side works better. To get around the lack of the handle mechanism, I altered the top plate of the Cube to take some M6 Rivetnuts and then used the original holes in the acrylic case top plate with some fancy M6 socket head screws to hold everything in place. The water loop in there consists of an old H80 combined pump and block to cool my i7 3770K, a modified XSPC RASA Gpu block to cool the half height Sapphire HD7750, an Alphacool 120 mm radiator, a Noctua PWM cooling fan in "push" mode to throw air out from the case through the rad fins and lots of 6mm ID fittings (to route the pitifully short tubing around the case). It uses 6 elbow bends and then probably a total of about 10 to 15cm of flex tubing - definitely a top contender for smallest ever CPU/GPU cooling loop! Total de-ionised water to fill the loop? About 250ml. As you'll see from the benchmarks though this loop is still enough to make this run really cool and is incredibly quiet. To make such a lot fit in such a small space I used three custom cut plates to bridge the cut-down original drive holder brace and the handle bracket and these hold the rad,fan and GPU in one solid unit from which the PCB is then suspended by PCB standoffs. To finish it off I had made a laser cut bottom plate with a honeycomb middle opening to allow as much air as possible to be drawn into the case from top and bottom (back and front now!) and feed the radiator so it can be ejected from the top of the case. The system is running on Mavericks and everything works. Bootloader was installed to the EFI partition and that solves issues that the HD7750 had with not wanting to boot, now it is working great. Final parts list: Zotac Z77 ITX board i7 3770K Sapphire AMD HD7750 low profile card Noctua 120mm PWM fan Watercooling elements: Alphacool NexXxoS UT60 Full Copper 120mm XSPC RASA GPU block Combined CPU block and pump from old H80 unit 6mm ID tubing and fittings Extras: 500GB Toshiba SSD; Compatible half height airport card; BT dongle. Finished Pictures Benchmarks Video [video=youtube_share;-SMZkWcbrdU]http://youtu.be/-SMZkWcbrdU[/video] On the second video you can gauge how quiet this machine is - I am using a webcam with an integrated mic and I am giving a whispered explanation of the lighting. The background noise is the sound of the Noctua fan and even more faintly the sound of the Corsair pump. Distance of the mic from the components is around 3cm from the fan intake and about 10 centimetres from the integrated pump/block….. [video=youtube_share;OjME8oJA22E]http://youtu.be/OjME8oJA22E[/video] Hope you like it! All comments welcomed…. CREDITS: Thanks to Fleisch for first using this GPU in a Cube build and bringing it to my attention; to my fellow modders for encouragement and inspiration (esp. Neilhart; Esterhernd; MacTester57) and all on the forums for sharing advice.