Try this one stick at a time.
Put the stick in the first slot and test.
Put the stick in the second slot and test.
Repeat with the second stick.
My computer is a HP Slimline S5-1010 from 2011. The max capacity of RAM is 4gb and currently I have 3. I tried installing 2 new sticks of Hynix 2gb 1RX8 PC3-10600U-9-11-A1. When I boot the computer up it just beeps, but when i put in the original ram (2GB & 1GB 2RX8 PC3-10600U-999 HF) it works perfectly and doesn’t make any noise. They seem to both be the same, but it just doesn’t work. Is there any way of fixing this?

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