I see that ram cards come in different sizes, some cards have 2 holes and some have 1 hole on the bottom of the card, I’ve noticed that some ram cards can have the hole just over the Centre of the card. What does CL3 CL4 CL5 mean, Does it mean where abouts the hole will be positioned. Please help

Answer:
Go to CRUCIAL.com……they'll scan your Personal computer…..check what you’ve,and tell you what you can add, price
Answer:
go here and do system scan