I assume '24MB' is a typo and you meant '24GB' of RAM. You may have a couple bad sticks. I would test ONE 4x4GB set at a time; see proper DIMM slots -> http://i1013.photobucket.com/albums/af254/Jaquith/ASUS_Quad_Channel.gif
In the BIOS, raise both the VTT and VCCSA Voltages = 1.20v and in Widows make sure MSCONFIG looks like (see image) - http://i1013.photobucket.com/albums/af254/Jaquith/Boot_OPT.gif
Update the BIOS to the latest version using ASUS EZ Flash 2; see - http://www.tomshardware.com/forum/289507-30-what-flash
Q - What OS are you running?
Q - What RAM is installed? please provide a link or links to your RAM
Q - Post a copy of your Resource Monitor; see below