Since all the new sticks are the same size, there should be nothing difficult about simply removing the old and replacing with the new.. (Make sure the sticks are pushed completely down and the clips on each end are closed.)
But if you're using a 32 bit operating system, you will probably notice that only 3.5 GBs will show as being recognized and usable. It's a 32 bit issue and is normal. It's not really a "pitfall" but it's something to be aware of.
On the other hand, if you're using a 64 bit OS, all 4 GB should show up.
Hope this helps.
Grif
I currantly have 4-512MB sticks of memory = 2GB in my pc.
I am going to replace them with 4- 1GB sticks = 4GB
I know how to physically do it but is there any techie things to watch for or do? Any changes to be made?

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