computer won't boot when HDD is plugged in?

jdaniel 125

Honorable
Jul 14, 2015
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10,690
im trying to fix up a tri core custom built AMD Athlon machine by re-installing Windows on it, but my only problem is, when the hard drive is plugged in. I CANT BOOT OFF OF ANYTHING! i can't boot off of a flash drive or a DVD, a blinking underscore just appears, I've tried 3 different hard drives, a SATA drive, and 2 IDE drives, when I boot up with no hard drive. I'm able to successfully startup from an installation disc or USB, but I can't when the hard drive is plugged in. the motherboard is a biostar A880G+. any help?
 

jdaniel 125

Honorable
Jul 14, 2015
214
0
10,690
guys, I have a new problem now. the computer won't boot up from ANYTHING. if I insert a DVD or USB, the flashing underscore appears, I tried using a Windows PE boot disc and a Windows 7 setup disc. the underscore still appears even though both discs and my USB drive with Windows 8 work perfectly on my other PC.