Thanks for the help. I managed to make the new Seagate drive boot up by itself without the present of the old 5200 RPM drive. Along with your suggestions, I found that the booting problem was because of some setting in the Bios. Setting the Primary drive 0 and drive 1 to both on "Auto" in the Bios will prevent drive 0 from booting up by itself. Leaving the Bios settting that way will generate a drive 1 not found error message. The system refused to boot up drive 0 b/c drive 1 is not found. Setting the Primary drive to "Auto" and drive 1 to "Off" allow the new drive to boot up by itself. I would've caught on to this quirk earlier if the Bios had sequenced the drive as 1 and 2, instead of 0 and 1. I installed a fresh copy of Window XP Home edition to hopefully reduce the drags in the system. I still have to find some quieter fans to replace the stock fans. If this system wasn't so cheap when I bought it, I would've made the manufacture eat the cost of the return & refund of the computer system.
I do have one more problem with this system. The computer would completely freeze when I try to use Microsoft Office to open a file in the floppy drive (A: drive.) The freeze is so severe that pressing Ctrl&Alt&Delete will have no effect. Pressing the On/Off button will have no effect. The computer will still stay on when I press the off button. The only way to reset the system is to pull the power cord out from the wall. I don't know why opening a file in the floppy drive would cause the system to freeze.