This PC I am troubleshooting was built in 2009/10, with some HDD&SSD swaps since then. everything else still from back then.
A month ago it hang up and had to be shut off manually. Didn't boot or POST since.
In the process of diagnosing (and hoping its the motherboard so it can be upgraded), it was determined that the motherboard is alive - the speaker signals when no ram is installed. When at least one stick is reinstalled, the speaker remains silent, fans spin, no boot/post.
Any thoughts as to why?
UPD1: tried switching channels/slots with 1 stick inserted, no go. The blue power light blinks with a pause (•--•--), fans spin up and slow down. Will probably have to try a new stick, as it would be easier than finding a donor or testbed.
UPD2: the startup config is mobo (DP55WB)+CPU (i3-530)+fans+(RAM (DDR3 10600)). I believe the memory controller is on the CPU. Presumably, the "no RAM" signaling when RAM removed rules out the CPU?
UPD3/4: got some hands on a PC3-12800 4gb plank (mine was 10660), installed in Slot0 - no effect. Memory controller dead?---the RAM was Single sided, not supported by the memory controller.
UPD5: put the jumper into setup, post card stopped at 24 - setting DIMM timings. After that went back to cycling 27 (RAM-related) and unknown post codes. Must be RAM