I'm in progress of getting an old backup server back in service for taking backups of my fathers computer. One of the upgrades, next to external storage, was to replace current 4GB memory with 4 x 4 GB memory DIMMS.
So after consulting the manual of my Asus M4A785TD-V EVO to see what memory was supported, I bought a 16GB Corsair memory kit.
To my horror, after installing the DIMMS, the server no longer boots!!!!!!
So I tried all kinds of DIMM configurations, reset the CMOS, removed the motherboard battery, unplugged all devices, BIOS upgrade, ... all to no avail
Major panic, sweat, sickness, anger,....
Then I noticed after the n'th test that when inserting the new DIMM's a LED flashed on the motherboard. Than it hit me, the DIMMS are situated next to the motherboard's power connector and when pushing on the power connector, it nudged itself slightly deeper into the socket.
Reboot
TADAAAAA a working system!!!!
Finally I can continue setting up this system. Lesson learnt: always check all connectors.