It is either that, with respect to your stated experience you are not folowing this procedure
To install Windows 7 on a computer without an operating system To do this, you'll need to start, or boot, your computer using the Windows 7 installation disc or USB flash drive.
- Turn on your computer, insert the Windows 7 installation disc or USB flash drive, and then shut down your computer.
- Restart your computer.
- Press any key when prompted, and then follow the instructions that appear.
- On the Install Windows page, enter your language and other preferences, and then click Next .
If the Install Windows page doesn't appear, and you're not asked to press any key, you might need to change some system settings.
- On the Please read the license terms page, if you accept the license terms, click I accept the license terms , and then click Next .
- On the Which type of installation do you want? page, click Custom .
- On the Where do you want to install Windows ? page, choose the partition that you want to install Windows 7 on, or click Unallocated Space if no partitions are listed, and then click Next .
If a dialog box appears saying that Windows might create additional partitions for system files, or that the partition you chose might contain recovery files or other types of files from your computer manufacturer, click OK .
- Follow the instructions to finish installing Windows 7 , which include naming your computer and setting up an initial user account.
OR I know you say you have removed the external drives and I think that you now have ONLY the one drive installed internally.
If I am incorrect remove the other drive from the IDE cable.
OR on some motherboard the boot priority is hard drive, but there is then a sub menu to select which hard drive, this is common on motherboards that have both SATA and IDE connections.
I would check that in the BIOS
Alternatively, although I cannot see why, if you have the jumper correct, I did send you the jumper configuration for the Maxtor drives, set the jumper cable select.
On a cable select IDE cable the position of the drive determines the master or slave as you know, when the drive is jumpered cable select
and in BIOS check if that drive is set to auto detect and if it is, after trying the cable select, if that does not work, set the hard drive up in BIOS according to the spec of the drive