Please help. Put a dvd-rw drive on a friend retail pc....

[elperra]

Hi. I install a Pioneer 110 dvd-rw on a friend compact retail pc, it reads the Pioneer ok but it doesn't detect the dvd-rom that came with the pc. I took out the cd-rw drive that and put the Pioneer in. I am going today to my buddy's home and will switch the drives to see if that works. But if it does not work, what else can I try? and why it doesn't read the dvd-rom any more?
Good thing I started to build my own computer .

 

[jeremy]

its a jumper issue look here http://www.techist.com/showthread.php?s=&threadid=96217#post739710

 

[elperra]

Thanks JEREMY for your info. I will do that today.