Yes, and no it won't if it's high % isopropyl alcohol
With 4 Titans, I'm rather surprised you didn't opt for 2011 for more PCI-E lanes. 40 with X79/2011, 16 with 1155/1150. Relying on PLX chips will hurt your bench scores quite a bit, which is what I imagine you have four of them for.
Depends on GPU and resolution.
Basically, it only makes a difference in multi-GPU configurations on multiple monitor setups. 690s get a bit of a boost, like a few percentage points.
No, there's been sort of a lost in translation here I guess. My Titan setup is a LGA 2011 mobo, and a Sandy Bridge Hexacore Extreme. My new Haswell build is the new Z87 Asus Sabertooth and Tri-SLI 780's.
Sandy Bridge Titan Setup:
Monitor: ASUS VG248QE 144Hz 1ms response time 24"
Antec Twelve Hundred V3 Full Tower Case
Corei7 3970X Extreme Edition Six-Core OC@4.8GHz (cooled with Corsair H110 water cooler)
ASUS P9X79-E WS LGA 2011 Motherboard
32GB of G.SKILL Ripjaws X Series RAM
Tri-SLI EVGA GTX Titans
1050watt Seasonic PSU
3x 2TB WD 7200rpm HDD's
1 3.5 WD TB HDD
2 Samsung 250GB SSD's
LG Blu-Ray Rewriter
Tons of 120mm LED fans all over the place
190cfm monster fan at my back exhaust
Haswell 780 Setup (final for now):
-Haswell 4770K 3.5GHz (@4.2GHz)
-ASUS SABERTOOTH Z87 LGA 1150 Intel Z87
-BenQ Gaming XL2720T Black 27" 1ms 120Htz
-Tri-SLI EVGA GTX 780 3GB
-3x WD Scorpio Blue 1TB HDD's
-Samsung 840 EVO MZ-7TE1T0BW 2.5" 1TB SSD
-Seasonic X-850 850watt PSU
-Koolance EXC-800 Portable 800W Recirculating Liquid Chiller (Not off Newegg)
-Antec Dark Fleet DF-85 Gaming Case (water cooling closed case ready) (Not off Newegg)
-LG Black Blu-Ray Rewriter
-Leopold Keyboard cherry blue switches
-Razer 2013 mouse
-32GB (4x 8GB sticks) GSkill Ripjaws X
And I just bought all the Haswell rig stuff not too long ago, so I've got to pay that off before I get anything further. Still have a leftover GTX 780 though, unwrapped with SP: Blacklist voucher attached. How much could I sell that for?