[Asus] A8R32-MVP Deluxe

So I have a problem I remediated a year ago and forgot exactly how I did it. I have an Asus A8r32-MVP Deluxe motherboard and while it works fine with 2GB of memory installed, the second I toss in the extra 2GB to bring it to a total of 4GB is where a memory conflict ensues and booting to Vista x64 ends up with the display device not even being detected. In its stead is a PCI-to-PCI bus conflict. I can't uninstall the device from device manager and have it detect a video card. So long as I have 4GB installed, the graphics card won't get detected, although with only 2GB installed, there are no problems at all. Has anyone found a familiar issue with this board and with the extra memory?