You get more help with more details. I can't guess the connections of the drives in question, if the power was connected and the drive jumpers set.
Then again the model you noted is now beyond the usual end of life. That is, many are dead. Isn't booting up good enough? I define booting up as all the way to Windows.
Bob
Just installed dell gx280 MB into gx280 using existing parts from my old gx280 including hard drive. The system starts boot up but does not recognize the HD or the DVD drives. System utilities shows no drives. I am lost here.
I replaced because I had had no problems with the Dell, but had not used it for three days and then it gave me "no signal" message when I tried to boot it up. I replaced the video card with brand new one with no luck. Still "no signal" It had worked fine until this. I had all green diagnostic lights except the top one was yellow. Using my other PC for the info, I went through the steps for Dell diagnostics and finally ended up with "other problem" as the diagnosis.
Again, this was a gx280 mb replacing a gx280 mb.

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