My 2008 quieter liquid cooled computer started to fail in 2014. (It had EVGA 680i motherboard, Intel E6600 Core 2 CPU, EVGA 8800 GTS graphics.) Wanting to be able to upgrade to a future 14 nm Broadwell CPU, I got a very nice ASUS Sabertooth Z97 Mark I. The Z97 chipset seems a relatively minor upgrade of the Z87, but does support Broadwell.
The Sabertooth includes a steel motherboard stiffening and cooling backplate that seems to greatly increase the rigidity of the motherboard and also cools the back side of the motherboard by several degrees Celsius by acting as a large heatsink connected to the hot parts of the motherboard. The top of the Sabertooth Mark 1 includes plastic shrouds over the hot chips and heatsinks and a couple cooling fans for those areas that are controlled by the motherboard. ASUS also claims the use of high temperature military rated capacitors, inductors and MOSFETs (all board-level power supply components). All in all, the intent is to offer a premium, reliable board, targeted at overclockers. I have no desire to overclock, but want a reliable system, which the added system toughness may help.
Deciding to go with air cooling for now, I reused my idle Antec P150 case for this system. The P150 was inexpensive but features very nice thermal and mechanical design. (In some ways it's a nicer design than the full tower P180/P182.) It's also a relatively small mid tower case, which is just fine since I had no intention of using (any/many) hard disks. For speed and energy efficiency, I'm using a Crucial SSD insead of a hard drive.
Temporarily using an Intel Celeron G1840, which is actually a 22 nm dual core Haswell without turbo or hyperthreading and with a relatively high clock rate (for a low end CPU) of 2.8 GHz. Temporarily using an ASUS Geforce GTX 750 Ti OC 2GB, which is the first Maxwell-based GPU product from Nvidia. Both perform more than adequately for normal desktop usage. Both are relatively inexpensive, though the GTX 750 Ti is overspecified for desktop use. Have not tried them for gaming, though both should be somewhat capable.
Using Corsair Vengeance 8GB Dual Channel DDR3 Memory Kit (CMZ8GX3M2A1600C8) because it's popular, relatively high speed, has big heatsinks, low latency, etc. Factory installed big heatsinks should be the best of both worlds: reliable (and reliably installed) and cooler running. 8 GB is plenty for desktop use, but have not tried with games yet. 4 GB would probably be enough for common desktop uses. Dual channel should be marginally faster than single channel, and it spreads the heat load over twice as much area, so should be more reliable, for a given size of DRAM chip. Lower density RAM may be lower technology and therefore somewhat less energy/heat efficient, but spreading even those over double the area should result in lower operating temperatures, which is usually better.
Thermal: the GTX 750 Ti has an oversized circuit board and heatsink with dual fans and is quiet. (The same chip is used on half length boards and a single fan in other implementations.) I replaced the stock CPU heatsink with an Arctic Cooling Alpine 11 PRO Rev.2 which is much larger, cooler and quieter.
I intend to go with a 4k monitor in future, and if I game with it will probably need dual high end Nvidia graphics cards. Waiting for Nvidia to finally get to smaller transistors than the current 28 nm, but that may not even happen in 2015. Also waiting for the socketed Broadwell quad core CPUs to come out, preferrably a T model with low clock rate, but high turbo boost. Everyone is having difficulty manufacturing smaller transistors, though Intel has a lead. It's very difficult to do.
It may be possible to fit a liquid cooling pump into the P150, with an external radiator, and I may end up doing that for a high performance 4k system. If so I'd probably use the Swiftech MCP655-PWM-DRIVE pump. Not sure what the best CPU liquid coolers are now. There are only a few factory water cooled high-end Nvidia graphics cards. ASUS has a model that can be either air or water cooled. On the other hand, air cooling is simpler and quieter for daily non-gaming use.
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