Since U opened the CPU to install the new memory modules first check ani power or data connections. Every time U turn on your computer every single device makes a Power On SelfTest, in CD Driver usually the leds flashes and some make some noise, think of them as the beeps the computer makes at every startup. If you see no led flashes or no noise in the CD you might the power cables. If the CD units seem to get awake then maybe your problem is the data cable. Check at the PC BIOS if the computer can autodetect the units (take note of the HD geometry before this and write it down, just in case) If the BIOS is unable to autodetect the CD units for sure either the power or the data cable are disconnected. If the BIOS actually can detect your CDs then someone else will have to enlight us. Good luck.