I have a three older first-gen Core i7 computers with the DX580SO motherboard. I am trying to upgrade them to the DX580G motherboard so they can sport 24GB instead of just 12GB of RAM. So I purchased new-in-box DX580G motherboards on Ebay and started the upgrade. The CPU is Core i7-920.
The first one worked fine, but the second one stalls on startup with postcode 14, which indicates LAN initialization. I have tried everything I can think of -- I systematically removed everything including RAM, leaving just the CPU in. I get two very quick chirps at startup, then it rapidly cycles through a few postcodes and lands on 14.
I have tried this with both of my remaining DX580G motherboards, both in an out of the chassis, and with two different power supplies. I've tried the Boot to BIOS switch and removing the BIOS jumper. I'm ready to try my third remaining CPU on the possibility that the CPU has gone bad, but I'm reluctant to take apart my third functioning machine until I've exhausted all other possibilities. The CPU was functioning before I took it out of the DX580SO motherboard.
I have seen advice suggesting that I remove the battery and power supply and drain the CMOS or to rewrite the BIOS from USB, but haven't given those options a try yet.
I would appreciate any suggestions -- thanks in advance!