always put VGA into 1st PCI-E slot. if you use 2 of them SLI etc, connect monitor to the 1st VGA.
your board don't have 2 PCI-E slots. you have tried with regular PCI VGA? if yes ensure 1st VGA is setup to PCI-E when using PCI-E VGA.
if no go can be due weak PSU, forgotten power cable to the VGA(if your VGA has it) or damaged VGA.
please read again the post, you are talking about a sli mainboard (mi motherboard only has 1pcie 16xslot), my motherboard has 3pcie conectors, all of my hardware is ok, besides the mainboard. now my vga is in this slot
for this reason my vga is only working at 2x (becasusse this port is only a 2x pcie, not link the tipical one, who is 16x)
so, my bios only gives me 2 posibilities for searching a vga:
start from pci: no problem at all, i was using a ati aiw 4mb pci vga with no troubles. if i enable this option and use a pcie card the system will hang has described
start from first pcie: if i use a pci vga, no problem, system works perfect (just like with start from pci). if i use a pcie card in the 16x slot, system hangs has described. if i use the same vga in the pcie 2x slot system work ok. what im asking is that maybe by "start from first pcie" the bios means it will try to boot from the first pcie slot from the pcie at the top.
hope i made this clear
i tried clearing cmos, that was the first thing i tried