Left PC for 3 months unplugged. Now it won’t post. I built my pc in around 2018, and it worked fine. 3 months ago, I had to leave the country so I unplugged the power supply and switched it off. The PC wasn’t placed beside a window. Now I’m back, plug it back in and it turns on but there isn’t any display. No monitor issue. I hear 1 beep every 3 seconds and the DRAM light is on. Looked it up and it was probably a memory issue. Took 1 ram stick out (I had 2 in). Beeping is gone but it still doesn’t post. Now the lights on the motherboard have changed. It goes from DRAM -> CPU -> DRAM. I tried switching out ram sticks. Still the same issue. Now I’m wondering if it’s a CPU issue or what? Does anyone have any advice where to go from here? Any help is appreciated, thanks! Update: thanks all for the advice, was able to fix it! I replaced the CMOS battery and reseated the ram. After much fiddling, I was able to single out ram #1 as the problem. I moved ram #2 up to the slot of #1 and my pc is now back running. I’m 1 ram stick less but I’m glad the problem wasn’t the CPU or anything. Cheers !