what shows that the computer is only using 1 MB (task manager, system properties, certain program)? If CPUz shows the sticks that is usually a good sign that computer at least recognizes the new memory. JEDEC speeds are different speeds that the memory can use/be set at to be more compatible with more machice... If there is only one that just means that the memory is set to be used in one configuration only.
I have a pretty old Compaq Pressario that was running 2 512 MB sticks so I added 2 1 GB sticks today but it still shows it only utilizing 1 MB. I put the new sticks in the original slots and moved the old ones over so it is not an issue of installation. I ran CPU-Z and all four sticks show up in the SPD tab but the 2 new ones only have values in the timings table under JEDEC #1, the 2 old ones have JEDEC #1, 2, and 3. I have no idea what this means by the way. Please help!

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