Only half the RAM shows
BIOS or Windows sees fewer GB than installed
What it means
One stick or one channel is not being counted, which points at seating, slot choice or the memory controller.
Common causes
- A stick not fully clicked in
- Sticks in the wrong slots for dual channel
- An over-tight CPU cooler or bent socket pins
How to fix it
- Compare the BIOS total with the installed amount, then reseat both sticks.
- Use the slot pair the manual recommends (often A2 and B2) and test each stick alone.
- Loosen the CPU cooler a quarter turn; uneven pressure can break a memory channel.
- Run MemTest86 and check the board's QVL list before buying a replacement kit.