I upgraded my system from a Ryzen 7 1800X to a Ryzen 7 5800X3D, replaced an RX 550 with a newer 16GB graphics card, and changed the power supply to a Corsair 750W Gold unit. The motherboard is a Gigabyte B450-DS3H. I previously used four 8GB DDR4 sticks without any problems, but after the upgrades, the memory only works in the fourth RAM slot. Any stick placed in the other slots causes the computer to repeatedly restart without reaching the boot screen. I already tried clearing the CMOS by removing the motherboard battery, and BIOS support for the new CPU has been updated. The CPU socket pins look straight. What should I check next?
3 Answers
Start with a thorough CMOS reset: unplug the PC, hold the case power button for 10–15 seconds, remove the battery for a few minutes, then reinstall it and boot with default settings. Test with one RAM stick at a time, then try two sticks in the motherboard's recommended paired slots. Four DDR4 modules can be more demanding, so confirm that the system works with a basic one- or two-stick configuration first.
If possible, reinstall the old processor and test the same memory slots. If the old CPU works normally, inspect the newer CPU very carefully and reseat it. If the old CPU shows the same behavior, the motherboard or its memory channels may have been damaged during the hardware changes. Also verify that the modules are fully latched and that the board is using default memory settings rather than an overclocked profile.
Check the CPU installation and cooler pressure as well. An overtightened cooler or contamination in the socket can prevent one memory channel from working. Loosen the cooler slightly and inspect the socket and CPU for bent or missing pins or thermal paste. Since the problem affects several slots, a CPU contact issue or a damaged motherboard memory channel is more likely than four bad RAM sticks.
The BIOS was updated when I installed the new processor, and I already tried removing the CMOS battery, but I’ll retest with one stick and the recommended slots.