I bought a PC with 8 GB RAM. I installed Windows 7 in it, and now its showing that only 3.9 GB of RAM are usable? What about the remaining RAM? Is
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Amazon.com: Dell Inspiron i3542-3333BK Laptop (Windows 8, Intel Core i3-5005U, 15.6" LED-lit Screen, Storage: 500 GB, RAM: 4 GB) Black : Everything Else
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