on your previos setup was the dvr108 the master and the samsung the slave?
if so did you set it up the same way on your new setup? if not check your jumper settings for each device.
the device at the end of the cable should be jumpered to master, and the drive using the middle connector on the cable should be jumpered to slave.
if windows is your os, are you able to boot into windows? or is it not detecting during p.o.s.t. and just locking up?
if its locking up during post it could be your jumper settings are incorrect or its taking the bios to detect them. i just put a new hdd and cdrw in a compaq and i was having problems with it locking up during post. everything was jumpered correctly.
i rebooted, had to leave and when i came back(2 minutes later) the bios recognized the devices and i was able to load up windows. it was a 750mgz amd compaq, i wonder if the slow chip was the issue? before this i had rebooted several times with no go with the same correct jumper settings.
also, if the above doesn't work, trying getting into your bios and under "standard cmos" settings or something like that, run "autodetect" or something close to that.
and lastly, make sure the molex connectors to both drives are inserted properly and make sure the data cable running into the drives is using the "secondary ide" slot and your hdd is using the "primary ide" slot.
hope this helps and post your progress.