IBM X3650 server ram recognized only 4 GB insted of 16 GB in OS.

HI ,

IBM SERVER - X3650 MT-M 7979-I2S

S/N - 99D9029

IBM x3650 server previously there was 4*512 GB ram installed and showing 2 GB Ram in operating system as well as in bios.

We have planning to upgrade the RAM , I have refer the ibm document and found it will supported up to 48 GB RAM with 512,1,2 & 4 GB memory modules.

I have purchase four 4 GB Ram and installed the same, first it was not recognized in bios as well in system, I have upgrade the bios firmware of that server and after that RAM detected in BIOS all 16 GB but in system it shown only 4 GB RAM.

OS - windows server 2003 32 bit