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#31
That is strange as I pulled up your specs last night and it showed a WD 360GB spinner hence me asking.
You said too that you used the first two slots just so I have it right usually with a four slot board the sticks are required to go in alternate slots ie 1 & 3 or 2 &4 depends on the board manufactures specs. My Asus for example uses 2 & 4 as the primary slots. As you say try each stick in each slot separately or together there are lots of combos.
Now as for the slots to clean them use a strip of old credit card about 1/2 inch wide nip the corners off one end hold a piece of thin lint free cloth over the end dab on some form of alcohol - iso propyl alcohol (what we swab the skin with before an injection) is good and GENTLY swipe along the slots.
This can also be done for the GPU slot/s.