Do You Have To Fill All Ram Slots Average ratng: 5,0/5 7830 reviews
Hi Guys,
I've got an Asus P5B Deluxe motherboard. Today I tried adding some new RAM to take it from 4GB to 8GB. The board is about 6 years' old. I've never used the black RAM slots before, only the yellow ones (2x2GB in slots 1 and 3).
My system only sees 6GB, not 8GB. I've tried various combinations of the RAM, get the same result.
To check the new RAM wasn't defective, I tried it in slot 1, a known good slot. All 4 sticks of RAM worked in slot 1, so the RAM wasn't faulty.
All 4 sticks work in every slot except slot 2 (the first black RAM slot). If I put any stick in slot 2 - old or new - the PC is dead, it won't even boot to the BIOS.
So it looks like I have a defective RAM slot.
Does anyone know of any way to fix this? The board is too old to RMA. I've tried an emery board down the defective slot, and I've tried squirting WD40 down it. No improvement.
Does anyone have any other ideas on how to get that bad slot working?
Thanks!
Without
  1. Additional Notes: For best performance, fill both memory slots, installing an equal memory module in each slot. The likely technical explanation here is that your MacBook (motherboard) supports dual-channel architecture and thus requires two identical memory modules. Benchmarks suggests that it gives a 5-10 percent performance boost.
  2. If you have single ranked RAM sticks (with chips only on one side) even on dual channel system you can still gain a tiny bit by having 4 modules instead of two because it will use Rank Interleaving (by writing alternatively on one Rank and the other) in addition to channel interleaving.

Do You Have To Fill All Ram Slots Without

Yes, you can have different sized SIMMs in the slots as long as each meets the needed speed for the given model. You may also be required into installing the smaller SIMM in a given slot. While you will have more memory to use the addressing will be slower.