I bought an Acer AM 5802 computer about 14 months ago with Windows 7 64-bit. Just before the year warranty expired, the DVD drive started to fail, so I replaced it. Just after the warranty expired, the graphics card, Nvidia GeForce GT220 1024MB, began to act up. Every time I used a full-screen application that had any 3D graphics, it would kill the computer after only a few minutes. The screen would turn black and the computer would stop, though it didn't power down. Restarting it would solve the problem, though I still couldn't use those applications. Then it would periodically begin doing the same thing just playing video on the web. I run dual monitors and every time the screen saver came on, it would switch to only a single monitor on being woken, requiring me to go change it back in the desktop settings.
I figured the card was starting to go, so I bought an XFX ATI Radeon HD 4650 graphics card with 1 GB DDR2 memory. It's a little older card, but it still met my requirements and it didn't break the bank.
When I went to install the new card, I removed the old card, and replaced the new one, just like the instruction manual said and I didn't touch anything else. When I booted up my PC, the Acer screen appeared as usual, but then Windows wouldn't load. Instead, there is a message that says: "CD-ROM Boot Priority...No Medium | Reboot and Select proper Boot device | or Insert Boot Media in selected Boot device and press a key".
At this point, I'm not quite sure what to do. From what I can tell from reading online, this usually means that the hard drive isn't connected properly. I hadn't touched the hard drive and it has been working fine, but I rechecked the connections anyways to no avail. I don't have a boot disk and I don't want to try reinstalling Windows. I also tried reinstalling my old graphics card, but it now results in the same message. Can anyone help? I'm just not sure what to try next. This hasn't been quite the plug-n-play experience I was hoping for.