Alienware Aurora - R1

Hi guys,

Here the basics, I have an Alieware Aurora-R1 running dual Radeon HD5670's.... Yes, I know, I should have upgraded them along time ago.  But, money always seems to be the issue.  It's time to upgrade finally and I wanted to check to see if anyone has put dual GTX 780's in an R1.  The PCIE ports are 2.0 x16 and I am not sure if the two 780's will saturate the pipes or not.  I've been slowly getting ready for a system overhaul, to include a fresh install of W7 Pro x64. 

- The overhaul will include two new SSD's (any recommendations for a good 6gbs Sata III Port PCIE Expansion card since the R1 doesn't have an S3 controller?)

- The two new graphics cards (not bought yet, as  I want to do proper research first)  If anyone has tried and failed with the 780's what is the next best option?  I'm sure just about anything will beat the two 5670s I have in there now, can't even get crossfire to work right, I want my Nvidia cards back....  I would even settle for a single 780 if that is all the system will handle

- A reset of the waterblock with AS5

- general cleaning. 

I know I have seen some articles on the MIO board when doing OS installs so I will pull those as well.  Can anyone point me to the best practices one for the R1?

Anything else I should look out for?

Basics on my system: Aurora R1 - Out of warrenty

i7-980X

24GB Corsair Vengence

Non-O/c'd / No Raid

two WD Velociraptor 300gb

New SSD's: two Sandisk Extreme / 240gb / Sata III 6gbs

New Video Card(s): ??? GTX 780 x2???

PCI-E Sata III Expansion Card: Undecided on model/manufacturer

Thank you for help in advance. 

Lonewolf