I picked up a PE2900 with 1cpu and 4 1g men sticks. Started the system and it was giving errors due to not seeing the raid drivea. Drives were removed. I did the reset for the nvram and cleared the raid configuration. Upon reboot the system is not posting or no vga by rear or front ports. It is not showing any errors on the front LCD,
Since the problem started after you moved hardware I suggest you make sure that you didn't knock something loose. Check the connections and make sure that you put the jumper back on the correct pins after clearing NVRAM. The jumper configuration should be in the manual on the server support page.
Dell EMC, Enterprise Engineer
I've actually taken the system down to no components. Receive "NO CPU" error. Added CPU back in canceling that error. Then receive "NO MEM" error. Add 1 single memory stick, going 1 at a time through all 4, restarting each time gave no errors.
I've also noticed that the usb ports are acting weird. I have a USB keyboard/mouse receiver that has a power indicator on it. When plugged in the front port the indicator is on, however pressing the caps, num or scroll lock doesn't turn on those indicators. If I plug it in any one of the rear ports the power indicator lights up for a second then goes out.
Of course still have no post activity on screen. I know that the usb keyboard / mouse as well as the monitor and vga cable are good as I have another server that I have connected them to and they work.
I'm thinking the motherboard will need to be replaced.
Update: Everything back together and would still not get a post. Turned off some other equipment nearby (on same circuit) and thought one more try before leaving for the weekend. Turned if off and on and it posts! So apparently it was not receiving the proper voltage at the plug to fully power the board. Guess it's time to call an electrician.