ASUS A8N-E rev:2.0

I have mobo who is normaly starting up with PCI graphic, but with PCI-e 16x it don`t. Of course I tried with another PCI-E graphic but nothing. I can hear that HDD is starting to boot Windows and music when widows is loaded.But no picture.
Is this problem related with PCI-e supply or something else? From where PCI-E is takeing its supply. I changed all APM-s on mobo just to be sure.