The contact the CPU-370 makes needs to emphasized a lot, it allows someone to get near-perfect TIM performance (like they would get from Indigo Xtreme or Coollaboratory’s liquid metal TIMs) from something less expensive and easier to use, like Prolimatech PK-1 or Shin-Etsu X23-7783D. Even with a poor performing TIM like AquaTuning Silver Grease, you get nearly the same final performance as you did with the CPU-360 and MX-2. That’s just incredible.
If there’s a downside to great contact, it’s that it can mask underperforming internals. I’m not saying the CPU-370 has ineffective internals, it has the best of the three I’ve tested so far, but not by a lot–it’s less than a degree ahead of the CPU-360 rev1.1 and Enzotech Stealth. As we test more blocks, I wouldn’t doubt if the CPU-370 gets passed in the “Best Mount” performance metric.
The CPU-370’s response to flow is also a small concern. While scaling well with high flow is nice, there is pretty noticeable fall-off at low flowrates. My preference is that a block be flow agnostic, but as long as a user is aware that the CPU-370 likes flow, then I suppose it’s not a big deal.
As for the mounting system, I think it’s great. In terms of ease of use, it’s second best on the market and is significantly more robust and reusable than the Swiftech mounting system in first. EK just launched a new “Easy Mount” mounting system to remedy their old, awful mounting system and I’ve been able to use it for the upcoming EK Supreme HF Ni review. Frankly, the Koolance one is still significantly better, and it’s not close. Of course it’s not perfect, so if I could improve the Koolance mounting system, I’d have the threaded posts pre-installed to the backplate on whatever socket mounting holes are the most popular, make the block tightening tool-friendly, and make it so that it’s easier to get an even and correct amount of pressure from each corner. That said, the level of ease of use and simplicity that it already has is great and needs to be matched by other block makers.
If you’re looking to buy the CPU-370, what do you get? Why should you buy it? Why shouldn’t you buy it? You get a block that makes such great contact you don’t need Indigo Xtreme for near-perfect TIM performance. You get a great performing block that has low enough restriction as to not be a concern at all. You get a mounting system that’s extremely easy to use and ensures that you have great contact consistently. You get a block that gets all the little things right–changing mounting plates is easy, disassembling and reassembly the block is easy, it’s fully plated, has great build quality, and the block has great barb compatibility. You should buy it for all these reasons.
Its known weaknesses aren’t very pronounced: the included TIM isn’t great; while its performance is top-notch, my gut says it’s not the absolute best; and it looks nearly the same as the predecessor. I can’t see those being deal breakers for many people, but one thing I can see as a deal breaker? The price. At $85 MSRP it’s not overpriced, but it may price itself out of some budgets.
Overall, the Koolance CPU-370 is a great performer on many levels: thermally it’s great, it’s not particularly restrictive, it makes tremendous contact, and it has a simple and robust mounting system that results in consistent mounts. The CPU-360 was my favorite block of 2010 and the CPU-370 is undoubtedly better–it makes big steps forward in contact quality and that brings a big improvement in thermals. Even when contact is taken out of the equation (with Indigo Xtreme), there’s a noticeable improvement with the internals as well, likely from the 1.5mm injection plate.
When you pair great performance with a great mounting system and that block also gets a lot of the little things right, you just have a great block and the CPU-370 is just that.
A big thanks goes out to Koolance for the CPU-370 sample and also to Enerdyne for the Indigo Xtreme ETIs used in this review.