I have a Precision T5500 that has been working fine and in service for several years. Last night I powered the machine down completely (and turned off the power strip). This morning I went to power on the machine and the fans all cranked up very loud (safe mode setting). Initially the number 2 diagnostic light and the HDD and Network lights were on - All solid and the machine did not go further to POSt. Even stranger was the power button was not responsive, the machine needed to be unplugged for it to turn off.
Upon plugging the machine back in the #2 light was off and only the NIC and HDD lights were on. I found that strange.
Currently the machine is striped down to the bare minimum - one 1GB stick of RAM in DIMM #1 (the RAM that came with the machine from Dell - DUAL IN-LINE MEMORY MODULE, 1G, 1333, 1RX8X72, 8, 240, UBE) and I have removed the 2nd CPU rider board and have put only the single original CPU on the motherboard (MODULE, PROCESSOR, E5607, 2.26, XWM, 80W - which also initially came with the machine).
I am very frustrated at this point since there is no change. The motherboard NIC is not plugged in yet the light is on. Same with the HDD light - even with no HDD's the machine should still POST and allow me into the BIOS.
At no time has the power light turned green or amber and at no time other than the first time this morning has any of the #'s 1-4 diagnostic lights turned on.
I pulled the power supply and swapped it with another known-good one (I have several of these T5500's) and the PSU works in other T5500's and other PSU's produce the same error in this machine. My only other thought is that the motherboard is dead??? Could that be possible given what I describe? The machine is plugged into an APC 5-minute BBU battery & surge protector. The only other information I can offer is that the machine has been running ESXi for several years with upgraded RAM, CPUs and packed full of drives and components (RAID cards, SSD's, HDD's, SATA power splitters to fit extra SSD's, 72GB RAM, Xeon 6-core X5650 CPUs, etc.) they are maintained, taken care of and I have three more in this exact configuration and all work fine.
I would appreciate any thoughts or suggestions as to how to properly reset the BIOS or get this thing back functioning again.