Try 1 & 4 & 2 & 4.

Correct... No Slot 2.

You will notice there is a physical gap between the first 2 slots. According to documentation there is No slot two. The slots are numbered 1, 3, 4, 5...

I know I'm not dreaming... I read this on one of the docs included with the Mobo. I found it 'strange' as well.

From the "Visual Guide" you would get the impression that if you want 16x on two graphics cards, you should occupy the first two PCIe slots. If you choose that configuration, the most current BIOS says the slots are 8x & 16x respectively.

If you trust the spacing on the Dual SLI connector, you would expect Slots 1 & 4 to give you dual 16x.

Can someone from EVGA answer this simple question?

-A

Got it working 16x / 16x on lanes 2 and 4, however my video cards have very little space between them.   Hopefuly a Bios Update will come out that will allow lanes 1 - 4 or 1 - 2 or 1 - 3 to be used 16x / 16x.   Thank you.

dmassi
Got it working 16x / 16x on lanes 2 and 4, however my video cards have very little space between them.   Hopefuly a Bios Update will come out that will allow lanes 1 - 4 or 1 - 2 or 1 - 3 to be used 16x / 16x.   Thank you.

Not so much for me. I get no video and the board doesn't finish posting. Z87 Classified.

I tried 2/4 again, and found that for some odd reason, the card in slot 4 becomes the primary card. So I've got my monitors plugged into the card in slot 4 with the other card in slot 2.

I'm running both my 1080p monitors off the card in slot 4.

My cards are ACX,
 
I have them running on lanes 2-4 however I had to disable an onboard vga option on Bios as sometimes my PC would start with no video, however it would go all the way into windows (I could hear Windows welcome sound).  I also selected PCI-E for primary GPU.
 
However even though I have them 16x/16x I seem to be getting poor performance on games.  As if it would require some adjustment on bios or something.  Are you guys getting the same issue?
 
I even have my auxiliary PCIE cable connected to my PSU and my second CPU 8 pin believing it might be under power.

with my classy z87 rig (bios 1.09) i am running 4 470GTXs in 3sli configuration, leaving the
4th GPU for phyzics, All PCIex lanes are x8 exept lane 3 running at 16x. I have no clue why lane 3
according to specs we get x16 on the first socket as a native pci ex  lane if only no ather socket is occupied.
The Haswell pci ex  lanes limitation is rulling here.
Why i do not use the
4sli bridge? Well nvidia Drivers, pitty do not allow 4sli config and this not new, All my preview rigs were all
EVGA 4SLIs and i came to 3sli + 1gpu for phyzics solution  since i was ending with 2sli and 4 gpus.Concerning your
instabillity you should consider if your psu delivers the 30Amps+ required for cards to run.
For your information i have the on board VGA disabled and pci ex in auto since ,another bios issue,i cannot change
the setting of my primary display unit, from auto to pcie ex, if board wants auto A U  T O

Dear Scarlet-Tech thanks for your valuable info.
i will connect the 3SLI bridge from bottom up leaving lane 1 not connected and will see
whats come up.(PCIx1Lane is disabled from the microswitches, no3 switch,and also from Bios)
Any clues why with 1.09 Bios i can't go into bios with neither the F1/F12 nor the Del button?
i have to clear cmos to enter
the mobo boots really fast, that is true, and during boot i am getting not only a pattern of beeps but the classi logo as well
with the following indexies on the right corner B2 B4 A2 any idea what those indexies mean?
 

.
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Dear Scarlet-Tech
thanks once again for the reply, under a truble shouting undertaken a few minutes ago
cons the PCI ex Lanes look what came up, at least with my mobo:
only pci ex no.1 delivers me video no other card is delivering, in  the specific configuration with
the 3sli bridge conected from bottom  up leaving the no1 card with no bridge connection.
 In safe mode, always when i am playing with display , and HDMI monitor cable connected to no1 card, i was unable to setup the intel s
dislpay drivers,nor the nvidia since the card was no crecognized at all,
 for your information it was vga genaral driver that was providing the display according to device manager,
according to set up message my "machine is not propperlly configured(also virtu app gives the same message).
Now with 3sli Bridge connected from top to bottom ,only card/Line  no2 runs x16 card no.1/no.3/no4 run x8 
Also nvidia drivers automatically configures cards  no.1/no.3/no.4  in 3sli mode (Note:no4 card is not interconnected).
i am unable to run 2lanes x16 with all pci ex. sockets occupied.Cons bios entry i will come later on pls.

I have only ever moved the BCLK 1 to 2 mhz at most honestly.  It seems to make all of the systems unstable from what I have noticed.
 
The 2x16 is ONLY going to work if the other lanes are not occupied.  The PLX chip is capable of of providing up to 32 lanes for the Cards, essentially doubling the lanes the CPU can provide, which is normally 16 total.  If you have 3 cards in the system, the most you are going to get is 2 at x8 and possibly 1 at x16.  
 
As for the F2 Key, I have always used it to access the systems, and that has been across 6 motherboards.  The Delete key was the other key that was available, but the F2 was always my go to for some reason.  After the Bios boot screen and the EVGA Splash screen, I can hit F1, F8, or F11 (don't remember which honestly, I usually just spam them) and access the windows safe mode, but I rarely do that.. 

 
 
dear friend Scarlet Tech i am running the mem just below specs, Haswell sackes,2000 Mhz 2x8G dual Channel @ 1.590 v vegeance pro.
Mayby i am, silicon lucky, may i am not.Only 10% of CPU prodused pass 4.7gs. my aim is 3SLI, 4GPUs  and  at least 1000Mhz overclocked.