1.5v ram in 1.35v slot
Laptop RAM upgrade (new RAM doesn't work in RVS slot ...
When I put one new RAM in the STD slot and an old RAM in the RVS slot only then it works.
R710 2nd CPU Install - E1410 | Page 2 | DELL Technologies
To install the new RAM, align the notch on the RAM stick with the ridge in the slot, and firmly press the RAM into the slot until the side clips snap into place, securing the RAM.
Ram Slots aspire E15 — Acer Community
I tried one stick of RAM in each slot. It booted correctly with RAM (4 BG) in the first slot, and reported that RAM correctly.