my computer Acer X3910, 4 slots for ram. two under the hard drive. so, I can only add one, I move the one and put it inside. It shown I lost 2 G. I move it back, still lost 2 G. I do not know whether is the slot damaged or the ram.
why don't you put them right next to each other? It may well be the outside slot is damaged but not likely, I would try insert the ram with the case on it's side so the motherboard is flat, that makes the ram much easier to install and may well be your issue.
I am finding it hard to comprehend your setup, is two ram slots directly under your HDD? i don't see how that's even possible.
I bought a new ram and put in one of the 4 slots. ( the outside two. It does not work. I know the slot has damaged. The other two slots under the CD and hard drive, I lift up a quarter inch, move the old one in and place the other old one in right next to it. It works. Now it showed 4G on property. I can return the one I bought. For sure the outside two slot is damaged.
why don't you put them right next to each other? It may well be the outside slot is damaged but not likely, I would try insert the ram with the case on it's side so the motherboard is flat, that makes the ram much easier to install and may well be your issue.