Why my PC can't use 2pcs of (2gb) RAM = 4gb RAM 64bit

[toiletpaper03s]

Why my PC can't use 2pcs of (2gb) RAM = 4gb RAM 64bit
they will restart or auto reboot after i put the 2nd RAM 2gb RAM.. to make it 4gb.. but if 1pc of 2gb RAM installed.. there is no any problem.. how can i find the "400mhz" in BIOS settings because theres only shows 667mhz and 800mhz.
how to fix this please help me 🙁
Same brand RAM same DDR2 Same 400mz
Pentium R dual core cpu E5200 @ 2.50ghz
RAM 4gb usable
64bit
G31 - M7 TE Biostar = Motherboard

 

[megamanx00]

A couple of questions, is your RAM the same? If it's not, your board should default to the slowest but that may not be happening. You should take one piece of RAM and try it in both slots. If it works in one slot but not the other then the slot on your motherboard is bad. If both sticks work on both slots then put one in, go to your BIOS settings, and set the speed and timings there rather than leaving it on auto.

 

[toiletpaper03s]

my speed and timing set into enabled, "default seting". not solved my problem 🙁 and also to change the settings of voltage to add 15/max .. still the same.. 🙁 what should i do ?

 

[megamanx00]

Exactly what RAM and motherboard do you have?