I bought the PC version of the ATI Radeon HD 4870 and flashed it with the mac ROM. Everything went fine. I then moved the original card to slot 2 and put the new ATI card into slot one. I connected the monitor to the new ATI card and booted up. I get the apple logo, but after that, my monitor loses signal. If i plug the monitor into the original card (which is now in slot 2), it works fine. The desktop shows up. Any ideas on what is going on here? Is there anyway to check what hardware is installed in the computer? Any utilities?