Upgrading a 2012 build into a 2015

[Canis Major]

Hello! first i want to share with u my actual build :

Asus P9X79 LE LGA2011/Intel X79/DDR3/3-Way SLI/SATA3 and USB3.0/A and GbE/ATX
Intel Core i7-3930K LGA 2011 Hexa-Core Processor 3.20 Ghz 12MB Cache
Intel Bxts13x LGA 2011 Water/Liquid CPU Cooling

Kingston HyperX FURY 16GB 240-Pin DDR3 SDRAM DDR3 1866mhz (2 x 8GB)
Kingston HyperX SAVAGE 480GB SSD SATA 3 2.5-Inch
Samsung 840 Pro Series 128GB SSD SATA 3 2.5-Inch

MSI GeForce® GTX 980 Ti GAMING 6G (x2)
MSI Gaming 4K Video 80mm 2 Way SLI Bridge
Acer Predator 27" WQHD NVIDIA G-Sync Widescreen Display (2560 x 1440, 144 Hz, 4ms)
EVGA SuperNOVA 1300G2 80+ GOLD (1300W)

I need some advice, since my 3930k only works in PCI 2.0 not 3.0 like will i have less efficiency? I only know some basics on pc build, but recently bough an other 980ti for SLI and a new Monitor.
I need some advice of wich part u would change to optimize my current built.
I tough about changing CPU-MOBO-MEMORY- but man my budget will blow.
- Wich Part would u change to get the most out of my cards and display?
- Should i be fine with my SLI and display with actual build?
- Advice on settings (BIOS- PCI 3.0, OC,) what would u be sure to check to get 110% out of it?
- 3930k work max DDR3 1600 should i OC to match my 16 GB 1866mhz memory?
- What would u check to be sure my 980ti SLI work 110%? Its my first time SLI and 27'' IPS 1440p monitor...
i dont know where to start.

Thank you so much for your help!

 

[dudeman509]

Really absolutely nothing is worth changing at this point. RAM speed makes almost no difference; PCIE 2 vs 3 makes no difference at all (literally 1-2 FPS at best) with current graphics cards.

If you haven't overclocked the i7 yet, go for it - play around with different speeds and see if you notice any kind of improvement in-game. My brother has a similar build with a GTX 1060 and the CPU isn't holding it back whatsoever.

 

[Canis Major]

hi dudeman509, Thank you so much for your answer, i did try to OC that CPU but it was very unstable, i decided to not touch it. But i might give it a retry. Wich program would u use to do so?

 

[Canis Major]

Got it clocked to 4.2GHZ with no problem, working like a charm