Have you cleared the BIOS? If not, clear your BIOS and try to restart with a single module installed in the proper memory slot for single module usage. If it boots OK, power off, then add the other 3 modules.
what is the new memory ? speed, etc. you have an old board. are you sure that memory will be supported ? and what about the voltages ? the newer memory might run at different voltages. and from past experiences sometimes the voltages need to be tweaked.