ASUS M4A88TD-V EVO/USB3 - AM3 Dead?

I’m running a system I built 11 yrs ago, and it just bricked.

Here are the specs:
MB: ASUS M4A88TD-V EVO/USB3 - AM3 - AMD 880G - DDR3 - USB 3.0
CPU: AMD Phenom II X4 965
RAM: 16 GB (4x4 Corsair XMS3 DDR3)
SSD: Samsung 840 Pro 256 GB (running OS only on it)
HDD: Seagate Barracuda 3TB for main storage
GPU: ASUS AMD RADEON HD 6770 1GB
OS: Win10
PSU: Seasonic Focus PX-850 80 Plus/Platinum

About 2 months ago, the PSU would fire up but there was zero video output…no BIOS boot, nothing, just a fan spooling up then going very quiet/idle. Did a RAM check and T/S to the CPU. Ordered a used AMD Phenom 970, and it fired right up. 35 days later, same problem. Ordered the used AMD 965 that’s in it now (came with thermal paste pre-applied), installed the chip…and nothing. No PSU fan spin, no SB Pwr light, etc.,…just a brick. I disco’d the PSU (Corsair 800), direct-wired a fan and ran a jumper to simulate the MoBo…neither the PSU fan/lights fired up nor the hard-wired case fan. Figured it died, and bought the PSU noted above. I jumped the MoBo and the new PSU fired up, as did the hard-wired case fan. Installed the new PSU in the system with only the MoBo, SSD, and GPU connected. Same thing as with the old Corsair PSU…no power, no PSU fans, no case fans, but now the SB Pwr light is a solid green when the system is plugged in. The Core Unlocker and Turbo Key II LEDs are a steady red when I flip the switches (normally off). I’ve cleared CMOS and performed the RAM check multiple times. All I can think of is maybe the original PSU gave up its ghost and took the MoBo with it. I know, I’m way overdue a system update, but I’m holding out until the pipeline opens up and DDR5 chips go commercial and the prices drop. I welcome any thoughts or T/S tips you all can offer to help keep this dinosaur viable for a bit longer.