I have a asus p5b mx motherboard and just bought two 2GB pc2-5300u-555 chips. I don't remember which way the one's I took out were facing and it seems I can click these in either way.
Does it matter which way they are facing when I put them in? How do I know?
13 Answers
There's a notch near the middle (you can see it on the photo below) but slightly offset that matches the slot on the motherboard, to ensure that it only fits one way, Just line it up.
If you can click them in either way then either you are using way too much force or something is seriously wrong. I would stop immediately and have someone more familiar with computer assembly take a look at what you're doing.
Whenever it matters which way you connect critical hardware,
there is always a notch involved to guide correct connects and prevent the wrong ones.
Besides, it almost always matters which way you connect.