I noticed the eBay RAM is 10600E and the RAM in my computer is 10600U. Does this matter ?Sounds like it's probably 4 1GB modules then, so I'd probably buy that lot of 10x 4GB modules for $16.92 I linked above, that'll put you up to the max, and then I guess you'll have spares.
Lot of 10 Major Brand 4 GB DDR3-1333 PC3L-10600E 2Rx8 1.35V DIMM Server RAM | eBay
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