System is a custom built, with all new components. CPU: Phenom II X4 945, Rev C MB: Asus M4A785T-M/CSM - 785G Chipset, DDR3 1333 max speed (1600/1800 "OC") RAM: 2 modules, Kingston KVR1333D3N9/4G 4GB DDR3-1333 PSU: Rosewill 630W Green Series
Assembled computer, and it will not POST with either single 4GB RAM module, or both, installed in any slot or combination of slots.
Installed one module of known-good Crucial 2GB DDR3-1333 in slots 1_1, 1_2, and 2_1, booted correctly in all three, allowed full install of operating system. System works correctly.
Okay, suspect bad RAM, right. Took both RAM modules home and tried them in another system - this one is a known-good Phenom II X3 720, paired with a Gigabyte MA770-UD3P which is also a DDR3-1333 board (also 1600/1800 "OC"). It was built with 2 modules of PNY 2GB DDR3-1066, which I removed. I installed each Kingston 4GB module separately, and also installed both simultaneously - and in every test the computer POSTed correctly, saw the correct amount of RAM, and booted fully into Windows 7.
Took the RAM back to the Asus board and it still will not recognize either Kingston 4GB module.
Both the KVR1333D3N9/1G and KVR1333D3N9/2G are listed on Asus' Qualified Memory list, and Kingston's web site indicates the KVR1333D3N9/4G as a correct part number corresponding to the Asus M4A785T-M. Asus lists the maximum memory as 16gb which obviously indicates 4x4gb=16gb therefore 4GB modules should be supported.
Any suggestions for further troubleshooting or workarounds to get it functioning with the necessary 4GB modules? Anyone else experiencing issues with 4GB Modules in their M4A785T-M boards? Thanks in advance!
Returned Kingston modules and purchased G-Skill modules, model F3-10666cl9s-4gbrl. Also 4GB on each module, also does not work. ASUS tells us we need to use a 1gb or 2gb module to set the settings within BIOS, and then remove it and install the 4GB modules. Did that, no change. Contacted G-Skill and they notified us "Unfortunately, that particular model motherboard is not compatible with 4GB modules. Although, ASUS is currently working on a BIOS revision to allow it. Once it has been completed, it will be posted on their website."