The 1850 doesn't support dual-core processors.   What type of memory did you install?  It requires Registered ECC, preferably 400MHz DDR2. Return to troubleshooting using only the original parts.  Try clearing the NVRAM using the jumpers on the motherboard.  There is a locking arm for the processor -  make sure that it is used to secure the processor in the slot (it cannot be attached to the heatsink when installed).  The first processor slot must be used; the second can only be used if the first is occupied and must be occupied by a processor identical to the first.  Remove any expansion cards.
Hi All   I recently purchased a Dell PowerEdge 1850 off ebay to play around with for my University course...   It was booting and 'screaming' the fans fine at first but after I replaced the original single core XEON with a dual core and added two more modules of RAM (2 x 1GB) it will no longer POST, and the fans will not work as fast or loud as normal... there is also a flashing amber light on the front on the right most light??   I'm new to servers so I'm not sure whats gone wrong?   - The CPU is seated fine and I have added new thermal paste. - I have swapped out the new CPU for the old one again - Tried seating the CPU in the spare socket - Reseated all 4 RAM modules (2 x 1GB and 2 x 512mb) - Reseated both HDD's All to no avail =( Hope someone has some idea as to what I've done wrong here =/   Many Thanks. AH.   EDIT: Also note that there is no video output on the screen?
PowerEdge 1850 wont POST =(