May be bad, incompatible or incorrectly installed RAM... check the MSI Memory Support list...
1. If your RAM is not in it: Try a different set or even a single stick
2. If it is listed: Make sure it is well seated in the Sockets
3. If it's listed and correcty installed: try a different set or stick of DDR3 (preferanly one that's in the compatibility list)
4. If 1 to 3 checked and still nothing: Double check your motherboard installation;
a) One standoff & Screw per mobo mounting hole.
b) That nothing is lodged under the motherboard grounding it to the case
c) Check all motherboard power connections
d) If you have video, reset the default BIOS settings.
5. If all checked out and still nothing, RMA the motherboard.
MSI FM2-A75MA-E35 Memory Support
http://www.msi.com/product/mb/FM2-A75MA-E35.html#/?div=MEMSupport
On Startup 3 Long Beeps, 1 Short beep. HELP [SOLVED: Replaced RAM]
http://www.techsupportforum.com/forums/f15/solved-on-startup-3-long-beeps-1-short-beep-help-539304.html