Move the jumper back ... it should not be used in the CLR position.  This is only used to clear the BIOS hardware/settings config ... once cleared, it should remain in the default position. The error indicates either a problem with your memory or a problem with your motherboard (memory controller).  Remove all memory ... do you get a 1-3-2 beep code?  If so, then put in one stick in the first slot, swapping to test each DIMM.  If it doesn't boot up with any of the DIMM's, then you will need to replace your motherboard.
i got a trouble when i moved a jumper from NVram defaut positon to clear position and than restart the server, but the server can not be boot.who can give me a   advice? I will be very grateful.
DELL PE2950 error E2012 and can not boot