P4VM890 + new videocard! No boot up!

Question

I bought a new video card - giga-byte HD 3650!
1st i go'ed to bios, and disable onboard card.
I uninstaled videocard drivers.

then i put videocard in slot.
I started pc, and there is no boot up, just blank screen and red hdd light!
I tired everything! Cleared CMOS too, and nothing!