Check BIOS settings. Also check if RAM is placed properly. Just give a try.
Listen Closely To Your PC
If you hear these during the startup of your PC...
1. Up to three beeps: there are some problems with your memory.
2. Get four, five, seven or ten beeps: send the motherboard to repair or go
3. Six beeps: either your keyboard or keyboard control chip is faulty.
4. Nine beeps: replace your existing BIOS chip.
5. Eleven beeps: facing external cache problems.
6. One long and two or three short beeps combination: a likely video card