VapoChill XE-II Specification
More cooling performance
The XE-II uses the a Danfoss TL4CL compressor, changed from the BD35F used in the XE and SE. The TL4CL is a 1/6hp compressor that's designed to be used with R404a or R507 PFC refrigerants. It weighs nearly eight kilos and has the capacity to hold volume of over 1.5 litres of expanded gas and a 600g liquid charge. Paired with R404a, as used in the original XE, it's got a tuned heat capacity of 150W at around 0°C.R507 is the chosen refrigerant in the XE-II. DuPont's specs for R507 show that it's a blend of gases, containing part R125 (pentaflouroethane) which has a boiling point of -48.45°C, and part R143a (1,1,1-trifluoroethane) with a boiling point of -47.6°C. The blend of gasses results in R507, an inflammable gas on its own but one which can become explosive in air at very high concentration (which would never happen in a house for example). It's non-toxic so if it leaks to atmosphere you'll be fine (unless you live with your VapoChill'd PC in a car boot!).
Using R507 with the TL4CL lets Asetek tune the XE-II for heat loads of 180W at nearly -10°C. So some 30W more performance at a lower temperature, just from a gas recharge and cap tube tune. Impressive stuff, and nice and simple for Asetek and Danfoss.
Compared to the LS's cooling curve, it's some way short of that unit's -30°C performance with a 250W heat load, but as dicussed earlier, an XE is significantly quieter and more suited to day to day running. The compressor on an LS gets hot you see, the XE/XE-II compressor less so.
Finally, the biggest change is that the cooling hardware is all driven from your AC mains supply, as it is on the LS. You don't need a PSU with an otherworldly amperage on the 12V rail for the XE any more. The LS's USB ChillControl runs the show (with XE-II firmware) and you're free to make use of a larger range of PSUs than you would have had access to, had Asetek stuck with previous ways of doing things. Decoupling the hardware and powering from the mains is a good thing.
Mounting changes
The XE-II's mounting hardware is an adaptation of that introduced with the LS, and I cheer Asetek for it. The original XE's mounting hardware for supported sockets was unsuitable for current processors and mounting strategies and it offered up little condensation protection in the long run.The new style of mounting, where you enclose the processor front and back with closed-cell foam, creating a cell around the CPU area for air to stay out of, works much better with high-output processors and in terms of condensation protection in general.
I'll show you the new evaporator assembly shortly.
The same chassis
Asetek have used the same full chassis for VapoChills since I can remember, and I'm personally not a fan. It's bigger than I like and its overall contruction, as necessitates holding a near eight kilo compressor above the mainboard area, using steel makes it less attractive to work with. An aluminium chassis wouldn't do to suspend the cooling hardware above the mainboard area, but changes could have been made to the stell chassis in the life of full-system VapoChills, to make it more attractive to the eye.Aesthetics are maybe my only real concern, though. Some people really like it and I must admit that it has grown on me over the years too. Let's take a closer look.