After a lot of too-ing and fro-ing, and some long lead times on bits and pieces, I've kicked off the ITX downsize project I've been wanting to undertake for about twelve months. The current rig has served very faithfully for a while now but it's big, hard to access and too heavy for me to get in and out easily if I need to. Time to downsize. The goal was to maintain GPU power, CPU power and RAM capacity as current, and maybe update storage to total NVME along the way. I'm balancing this with GPU upgrade and NAS replacement projects, so budget was tight and on trickle-feed. Lead times were huge, but I only have some small electrics enclosures not here yet - final parts for cooling loop proper arrived Friday. Sourced Components: ASUS Strix Z270i Motherboard Thermaltake Suppressor F1 ITX Case Samsung 950 Pro 512GB SSD PrimoChill Advanced LRT Tubing 3/8", 5/8" (black, clear) Thermaltake QDC Fittings (two pairs, chrome) Lian Li Strimer ARGB MB / GPU Cables XSPC Photon 170 Glass Reservoir Retained Components: Intel i7 7700K CPU G.Skill 32GB DDR4 3200 (2 x 16GB) Gigabyte 980Ti with EKWB Block Samsung 960 EVO 250GB SSD Koolance 380i CPU Block EVGA SuperNova 1000 P2 PSU (with CableMod kit - black) Swiftech D5S (Strong) Pump (and AlphaCool D5 Top) HardwareLabs SR1 420mm Radiator Monsoon Compression Fittings (chrome) The EVGA DG-87 is an excellent case and I've enjoyed it immensely to build in and admire. It has room for eight 140mm fans at full capacity, and has a six-channel controller onboard. I cut off the stock thermoprobe (meant for air temps) and wired in a G1/4" plug to allow the onboard temp display to monitor coolant temperature. The AORUS Z270X Gaming 8 board will also be retired - apart from lacklustre overclocking the board has been excellent and is still probably the sexiest motherboard I've every bought. I'll also do away with the EK ZMT tubing this time - I love it, but I think I've decided on clear tube with chrome fittings for inside the new box. I've had the Monsoons sitting aside for years and always hung onto them - obviously for a reason. The NZXT gear is also going the way of the dodo here, and I'm not overly fussed. While the centralised control has been good, the Aer fans are over-rated and CAM's D3D overlay compatibility was very sparse. Otherwise a serviceable arrangement - they were first-to-market with a proper all-in RGB control system, and I was impatient. CAM offers good info and control besides the game overlay - it does phone home a lot, though. Tracking down an ITX Z270 board was tricky - well not tricky, but expensive. Thank goodness for timely eBay coupons. Of course the week after I bought it two popped up here, but ah well. First job was to gut the F1 and make it ready for an external loop. You just need an in and out port - in the past I've also run 12V to the external gear from the PSU, but as I'm running more electrics than I need outside the box I'd like the loop to run independently of the PC, so I'm powering externally this time. While I was going, I plumbed in a Type C 3.1 port to the rear to make use of the Z270i's onboard header. Here's a fitting pair. Thermaltake QDC straight into Monsoon compression. The case steel was just the right thickness to plump out the o-rings and make this a very tight fit. I was hoping to avoid bulkheads and did - win. I'd not seen the TT QDCs before finding them in FS - they're very good and restriction seems low on the test loop. Holes next. I wanted a super-subtle offset for the pair to allow for better finger tightening, so the fittings are slightly vertically unaligned. USB 3.1 port under the lower fitting. Passthrough ports in. Snug as a bug, USB port needs paint touching up around the edges, but I don't really mind at the back. I did wipe the texta off . Next was to blow the crap out of the case from drilling and Dremeling, and make a decision on new storage. Lots of parts were ordered in between - board, LEDs, PSUs, switches, RGBs, enclosures - pretty much everything I was missing. I also dummied up the desk loop, but am winging it as I go in reality. The desk is a compact corner unit with thin sheet metal undersupport and a veneer top - easy pickings. I'll mount the 420 horizontally on the RHS undersupport and cut/screen a rear exhaust vent. Fans (Phanteks F140SPs) on the front to blow air front to back. Thermoprobe in the exhaust stream for giggles - the temp display I got is a duallie, so I may as well fill the second channel. Fans will be connected to a cheap Temperature Controller PCB. I've used these in the past - configure the DIP switches to give you either a %20-100 or %40-100 duty cycle range and a 35, 40, 50 or 60C ramp temp, connect a thermoprobe (50K Ohm resistance for this one, not the usual 10K Ohm for PC WC stuff), fans and power, and away you go. Works well for very simple single-temp control. In my case the reservoir will house two thermoprobes - one for the fan controller, and the first channel from the dual front-panel display. The front panel display uses 10k OHM thermoprobes - not an issue, a normal G1/4" plug will work here, but I'll have to shoehorn a 50K in there too. I did pick up a 50K plug, but converting it out to BSP will be messy and more of a pain than drilling and sealing a stop plug - so that's where I'm heading. Also under the desk will be the pump and reservoir, and a 12V 10A brick to handle the external stuff. The pump is a Strong, so it wants the better part of 3A, and the temp controller and fans will use about 4A total. That leaves me a good 3A for LEDs, displays and lit switches. There's a 30A PSU on standby, but I'm avoiding having a sparky wire it up if possible, and the 30A one needs a direct 240V feed - no thanks. Electronics will go in a pair of cheap plastic enclosures - this'll be the DC inlet jack, lit switch for loop on/off, LEDs for feed and reservoir, temp controller PCB, front panel temp display and a separate feed for the pump with its own lit switch.