Say you have 2 2-GB 3-slot 6950 cards, which you plan to crossfire.
You plan you crossfire it on a p8p67/p8z68 MoBo.
You decide to put it in the Black and Blue x16 lanes(x8/x8 in CFX) - will the blue "thing" between the CPU and the blue lane bother/block the 3-slot card?
will a 3-slot card in the blue slot, together with a Noctua NH-D14 fit on the same mobo without bothering one another, even fit?
The concern is the problems keeping the systems rock 'stable' with the 2133 MHz RAM. The increases are only during obscure threaded tests. So my recommendation comes also from experience, and risking a BSOD during heavy gaming trumps fractional gains in limited environments.
The LGA 1155 Sandy Bridge's issue IMO is the fixed BCLK/DMI speed, the SB-E so far doesn't seem to have that limitation nor the prior Intel/AMD CPUs where you could increase the BCLK/FSB to alleviate the disparity in speeds.
In the beginning I was a 1866 & 2133 'pusher' but there was too much blow back and problems. Your Crossfire suggested heavy gaming...
Trust me 'I get' what you want - if you look at any benchmarks, the ones I've seen, the 1600 CAS 8/9 is like a wall on LGA 1155/SB - for Gaming. The cheapest way to increase FPS is duh OC both CPU & GPU, but after that spend the money on the GPU. If not the GPU then a ultra fast SSD e.g. OCZ Vertex 3 Max IOPS.
Since very few builds are 'budgetless' save the money and upgrade your GPU. I can GUARANTEE more FPS that way
I copied/pasted you this from an earlier post of mine to really think about; I'd take the cheaper setup ALL DAY!!!
22.3 % (SLI) increase in minimum frame rates w/ C6 instead of C8 in Far Cry 2
18% (single card) / 5% (SLI) increase in minimum frame rates w/ C6 instead of C8 in Dawn of War
15% (single card) / 5% (SLI) increase in minimum frame rates w/ C6 instead of C8 in World in Conflict
Even the bit-tech article shows the fastest performance at the CAS 7 1866 modules. The on game which they tested with showed the CAS 7 at 4.5% faster than CL9 DDR3-1600. CAS 7 DDR3-1600 is $40 more than the lowest price CAS9's. That's amounts to:
$2000 system - 2.0% increase in system cost
$1600 system - 2.5% increase in system cost
$1200 system - 3.3% increase in system cost
$1000 system - 4.0% increase in system cost
So even in a $1,000 system, you are getting more performance per dollar with the CAS 7's.
2. The DH-14 does real nice on the older LGA 775 chipset (frostytech.com's platform of choice) but who's buying those CPU's these days ? The LGA 775 has a completely different heat signature than 1155/1366 so I'd look for reviews on those platforms. BMR (who tests using 1336 platform) putsthe DH-14 in the 2nd tier as far back as November. Even the Scythe Mugen 2 which is half the price beats the DH-14 by 1C
If ya wanna spend $80 and up, I'd look at the V6 GT ..... It's the top cooler tested to date at BMR except for the Antec Kuhler 920 which is a self contained water unit. Both however, are quite loud. If dead quiet is your goal, the Thermalright Silver Arrow or Archon are excellent choices.
3. Given the $$ spent on other parts of the system, I'm surprised at the choice of the 6950's. I am assuming a 1920 x 1200 120 Mhz monitor and at that resolution, I'd be choosing the 900 MHz 560 Ti's (862 fos in SLI) over the 6950's (759 fps in CF for the OC;d Frozrs)
Guru3D uses the following games in their test suite, COD-MW, Bad Company 2, Dirt 2, Far Cry 2, Metro 2033, Dawn of Discovery, Crysis Warhead. Total fps (summing fps in each game @ 1920 x 1200) for the various options in parenthesis (single card / SL or CF) are tabulated below along with their cost in dollars per frame single card - CF or SLI:
I been having great luck with the Asus ENGTX560 TI DCII TOP/2DI/1GD5's getting almost all of them to OC to 1000MHz w/o any voltage adjustment whatsoever. Given the over sized coolers provided, no temp issues either.
However, if you go w/ a 2560 x 1600 monitor, I'd do the 2 GB 69xx series.
The RAM Article http://www.anandtech.com/show/2792/2 is for the older i7 9xx and LGA 1366 platform the OP wants P67/Z68 Sandy Bridge. edit: the i7 9xx and LGA 1366 allowed for BCLK OC, the LGA 1155 does not - and yeah, I run 2000 MHz RAM on my i7 980X However, the SB sees no benefits
Basically BOTH articles overlap findings that 1600 MHz vs 2133 MHz, Gaming, and Sandy Bridge offer no benefits. My 'feeling' is the SB-E LGA 2011 will benefit because of the BCLK/DMI OC -- that is assuming the specs I've seen don't change -- I've seen the LGA 2011 listed both ways NO OC BCLK & YES OC BCLK.
Jack - thank you for your post. Interesting reading.
Cards: The reason I favor the 6950's is because of it's ability to efficiently farm bitcoins, in addition to performance in gaming. The benchmark results have impressed me when it comes to crossfire.
CPU Cooler: I see on frosty tech that it was indeed based on 775 chipset. But does it really change the results so much? From many reviews from other sites that I have read, the D14 topped the charts. About the benchmark review; They don't use a sandy bridge based system to test the coolers.