Error 22/78 detected on X470 GAMING M7 AC with LED indicating CPU issues
Error 22/78 detected on X470 GAMING M7 AC with LED indicating CPU issues
Specs Motherboard: X470 GAMING M7 AC CPU: AMD Ryzen 7 2700X CPU fan: the one included with the CPU RAM: 2x8GB Trident Z RGB F4-3000C14D-16GTZR GPU: Sapphire Radeon NITRO+ RX 580 8G G5 SSD: CRUCIAL P5 Plus 1 TB SSD M.2 via NVMe PSU: be quiet! Straight Power 11 Gold (wattage unknown) The PC I purchased second hand from eBay three months ago came without any storage, so I installed the SSD myself right after bringing it home. For three months it ran smoothly. I acquired 2x16GB Trident Z F4-3000C14D-32GTZ RAM sticks second hand from eBay intending to fill the remaining slots. Instead of filling all slots at once, I swapped the RAM I already had with the new ones to test recognition in BIOS and performance. I filled DIMMA2 and DIMMB2 with the 16GB units. After attempting to power on, the system refused to start. The CPU EZ debug light was lit and debug LEDs displayed code 78 (ACPI module initialization). I removed the two recently added RAM sticks and reinserted the 8GB units. Nothing changed. I then tried booting with just one of the 8GB sticks in DIMMA2, but it still failed. I attempted using the other 8GB stick as well. Eventually, I cleared CMOS via the motherboard’s designated button and removed the battery. That also didn’t resolve it. I proceeded to flash BIOS versions using BIOS flashback+. I updated to the latest (E7B77AMS.1I0), then the older one (E7B77AMS.100) and the pre-install version (E7B77AMS.130). The only difference was the error code changed from 78 to 22 (OEM pre-memory initialization). The final step was trying various RAM configurations—all at once, then one at a time in different slots—and ensuring the CPU power connectors were firmly seated. What others reported online suggested either disassembling and rebuilding or carefully handling the CPU during debugging. I read about fixing the LED issue by dismantling the whole system or by removing and reinserting the CPU. I’m hesitant to proceed now, as I’m in the middle of an exam. It’s odd that the CPU seemed faulty despite only adjusting RAM. I searched for posts mentioning error code 22 alongside the debug light, but none matched my setup. While debugging, I didn’t hear any beeps from the speaker except when attempting a boot without RAM. The PC never displayed the required one long beep to confirm POST. Here’s a BIOS screenshot from the original owner. The only change I made in BIOS was enabling the second XMP profile, which worked flawlessly for three months.