3-Way & 4-Way on Z87

[adnank77]

I've done some research and here is what I've got:
- Z87 has 16 PCIe Lanes as a total.

- If I use 2 Way SLI or Crossfire, the graphics cards work as 8x/8x

- If I use 3 way crossfire, the graphics cards work as 8x/4x/4x .. SLI doesn't support 4x so 3-Way SLI is not supported natively on Z87

- To achieve 3-Way and 4-Way SLI and CrossFire in Z87, a PLX chip is needed.


Questions are:
- What does the PLX chip do and how does it distribute traffic between lanes? Could someone please refer me to a link where I can read some details ..

- Any drawback of using it? I keep hearing that native is better, but better why?

- If I have dual graphics cards running as 8x/8x .. theoratically I'm consuming all the Lanes .. Can I add a different card (e.g. PCIe SSD or Sound Card) or do I still need PLX for that ?

 

[MiRai]

What does the PLX chip do and how does it distribute traffic between lanes? Could someone please refer me to a link where I can read some details ..

I believe there are some technical details here:

http://www.plxtech.com/products/expresslane/pex8747

Any drawback of using it? I keep hearing that native is better, but better why?

I don't have an answer for this, but I've heard the same thing.

If I have dual graphics cards running as 8x/8x .. theoratically I'm consuming all the Lanes .. Can I add a different card (e.g. PCIe SSD or Sound Card) or do I still need PLX for that ?

On an 1150 board w/o a PLX chip, I would assume adding a third card which takes up a slot on the motherboard is going to drop one of the 8x slots you're already using to 4x.