Replacement DVD drive not being recognized.

Hello, I got my grandparents old PowerPC Mac mini after I replaced it with a newer iMac and have been replacing and upgrading parts periodically. Well I got a SuperDrive to replacing the cd drive that was not working very well. After I replaced the drive the Mac won't recognize it I put a disc in it spins for a while but no mount. So I put the old drive in and that won't mount anything either I have tried resetting the pram and PMU but to no avail. Any idea as to why I can't get it to recognize anything? On a side note the drive is a UJ-875 which is what you get here, but since the drive is not recognized by the mac the eject options are not avaliable like hold mouse or eject key on startup, terminal eject, and stopping the disc from spinning to make it eject (like I can with the original drive) so the only way to get the disc was to open the drive and remove it.