So, I've been meaning to post an update on the build but got lazy after finishing it last week.
The only major change was that the 7950s were swapped out for a pair of 7970s. I originally ordered a pair of XFX 7950 DDs since they were on sale at Amazaon based on TR's review which said that the DD Black Edition was a reference board:
TR wrote: This card is based on the same circuit board design as the reference cards—board makers haven't yet had a chance to build enhanced or cost-reduced versions of the PCB—but otherwise, it has been transformed with XFX's own cooler and a swanky custom expansion slot cover with a red DVI port.
It turns out, my Razor 7970 waterblocks (supposedly compatible with 7950s) won't fit on the 7950 DD. Either the regular DD uses a non-reference PCB or there are TWO reference designs for the 7950 - one based off of a modified 7970 and the one the XFX DD Black Edition used. My guess is that there are two. In any case, I gave them to my brother and bought some HIS 7970s which were the lowest at Amazon at the time. The blocks fit perfectly on these guys.
After slaving away for a few nights to get everything right, I get this:
No case permanent case modifications (i.e. cuts) were made. I removed the SATA dock, ditched one of the HDD bays, moved one fan to the outside of the case and that's all I needed to get all the rads inside. I also added an externally mounted outtake fan where the dock used to be. Zip-ties, twist-ties, and double-sided tape proved to be very good friends in this build.
-idle: mid 20s to low 30s depending on ambient
-load: high 50s to low 60 depending on ambient
GPU (Core @ 1125, Mem @ 1575, 1.2V)
-idle: high 30s
-load: high 50s to low 60s using FurMark. 50 C or less in most games (played mostly bf3). Worth noting that these cards were hitting 90C+ in BF3 with the stock HSF installed at stock clocks. Cracking the HSF off to install the waterblocks showed me that the technician who assembled them put WAAY too much TIM - obviously that isn't an issue now.
Both on load:
CPU - high 60s
GPU - low 60s
Ultimately, the temps aren't quite as low as I'd like under "high stress" conditions but under regular conditions, I think this loop works just fine.
2600K @ 4.8GHz; XSPC Rasa/RX240/RX120 Phobya Xtreme 200; Asus P8Z68-V Pro; 16GB Corsair Vengeance 1333 C9; 2x7970 OC w/ Razor 7970; Force GT 120GB; 3x F3 1TB; Corsair HX750; X-Fi Titanium; Corsair Obsidian 650D; Dell 2408WFP Rev. A01; 2x Dell U2412m