Beta Orionis – Part XX: New loop

Build Log:

First a recap on the current parts of the system, starting with the base parts.

  • CPU, mainboard, RAM: AMD FX-8350, ASRock 990FX Extreme6, 8 GB
  • Graphics: PNY GTX 770 4GB (2 in SLI)
  • Power supply: EVGA 1050GS
  • Case: Corsair 750D

And the water cooling system:

  • CPU: Koolance CPU-380A
  • Graphics: Watercool GTX 680
  • Radiators: AlphaCool UT30 — 3x120mm (1) and 2x120mm (2)
  • Pump: Koolance PMP-450 with AlphaCool HF D5 clear acrylic top
  • Reservoir: Phobya Balancer 150 Silver Nickel
  • Tubing: Type L annealed cooper, 1/2″ OD
  • Fittings: PrimoChill revolver, Koolance 90-deg, Swiftech SLI fittings, a few others

A few things about the loop will be changing:

  • CPU block: EK Supremacy EVO Copper Acetal
  • Reservoir: PrimoChill CTR Phase II D5 enabled
  • Voltage regulator block: Koolance MVR-100
  • Northbridge block: Watercool Heatkiller NSB 3.0
  • Southbridge block: Watercool Heatkiller SB 3.0

As mentioned in the previous article, the pump and reservoir will be mounted externally. To get the power through to the power supply, I ordered a power bracket from Amazon. But let’s start off with a little potential “oops”.

Wrong block?

In the list above you’ll see how I ordered the MVR-100 with a 140mm extension plate. Well, the 140mm plate was definitely not necessary, and it seemed the MVR-100 was going to be too large. Now the plate is 100mm long with 92mm between the centers of the mounting holes. In the interim I wondered if this would fit.

The ASRock 990FX Extreme6 mainboard is basically the Fatal1ty 990FX Killer without the upgraded network card — as one person discovered, they actually tape over the Fatal1ty logo with an Extreme6 label before selling it. But this means that finding a picture of either board to use for measurements should give me an idea of what I’d need. And I managed to find a review of the 990FX Killer board in which they removed the heatsinks. Lucky day it’d seem.

And it’s a tough call. Attempts at measurements from the photos show the block being a tight fit. I knew from another online post that the MVR-100 fits the Extreme9 mainboard. But the Extreme9 mainboard also has a longer heatsink based on measurements from images, so I’d expect it to fit. In fact it wouldn’t surprise me if it barely covers all of the VRMs. But I have another option: MVR-40 with an 84mm extension plate. But then the question is whether the 84mm plate would be long enough.

Of course I can shortcut this entire discussion by doing something similar to the previously-linked instructions for the Sabertooth 990FX R2.0 board: modify another plate. It wouldn’t be the 140mm plate I bought, because that’d be a little too long and can only be mounted to the MVR-100, which might already be too long. Instead I’d look at getting the MVR-40 and the 107.5mm extension plate, and drill a hole closer to where I’d need it to be so I could properly mount the plate.

Now the 40mm block combined with a nearly 70mm longer cold plate isn’t going to provide the greatest cooling — I’d prefer the 100mm singular block if I can get it to work — but some IC Diamond between them should help things perform a little better, with Liquid Ultra probably being the best for it. So that is the route I decided to go with the order: buying the MVR-40 and adding the 107.5mm plate to it. I needed additional hardline fittings anyway for this — I ordered two sets of four on those just to be sure I had plenty. And the rush order fee for Performance-PCs was a great way to push the order over the $100 threshold for PayPal Credit to defer the interest.

Having both options available will be good when I actually take everything apart. If the MVR-100 fits and can be secured without concern, then I’ll use it. If I can’t get that secured down, then I’ll have little choice but to modify the 107.5mm plate and use it with the MVR-40.

Figuring out the loop

Okay let’s see if I can figure this out. One idea that cropped back up that I touched on during the original build was using acrylic tubing for the graphics cards. And I had purchased the fittings to do it, but decided against it because I didn’t have a proper mitre box. Thankfully Michaels had what I was wanting, and I picked one up, but that was after the build was finished and I never got around to doing it again.

If I leave the graphics cards in parallel, or even if I drop down to serial, I can do this. The issue is the southbridge chip cooler. Basically the way I’m seeing the loop is the southbridge goes to the outflow while the inflow goes to the lower graphics card — the rest just goes from there. The southbridge chip is centered right behind the second 16x PCI-Express slot, meaning the southbridge cooler is actually not an option — I can’t mount it and retain clearance on the second graphics card.

This might actually push me back to the Gigabyte board, as the southbridge on the 990FXA-UD3 isn’t centered behind the 16x slot. I could use the NSB cooler on the southbridge and the SB cooler on the northbridge with that mainboard. That’d just mean setting aside the Extreme6 board to use in a higher-performance server with an FX-8320 or FX-8370E processor in a 3U chassis so I can use an AIO to cool the processor and a spare full-size power supply to run it — which is what I actually planned to do with the Gigabyte board.

It’s a consideration, at least. I moved away from the 990FXA-UD3 due to how it operated when overclocked. But since I have a heartier power supply, I may not have the problems I did previously. And the whole point of going this far is to see how much of an overclock I can get.

If I stick with the Extreme6 board, then the loop is pretty well figured out. The graphics cards will still run in parallel with the inflow and outflow beneath the cards. The inflow would go to bottom, front, then top radiator, to the CPU, voltage regulators, northbridge, graphics cards, then back out.

If I switch the mainboards, then the southbridge would be part of the flow. I could still keep the graphics cards in parallel, but that would complicate things. The inflow would still go to the radiators first, then the CPU. From there I’d probably take it to the northbridge, then the voltage regulators, then the top graphics card. From there it’d go to the southbridge, then second graphics card, then to the outflow.

It sounds complicated, but I don’t think it’s going to be all that bad. There’s another slight complication to changing the mainboards though that might also end up working out in my favor: the MVR-40 and the 107.5mm expansion plate may not be needed. But the voltage regulators on the Gigabyte board would potentially be more difficult to cool without doing something a little custom — likely involving modding the 140mm plate in the fashion similar to the Sabertooth board.

So the question is definitely what I’m going to be doing. I’m leaning toward the Gigabyte board, in large part because I can prepare the board before disassembling everything else. I already have the chipset blocks and the MVR-100 with the 140mm extension plate. The next order with the fittings arrives next week, so we’ll see how things pan out then.