Windows 7: How do I delete Win7 from old, second HDD?

I have just installed a 1Tb Western Digital HDD in my PC with Windows 7 Ultimate x64. My old 185 HDD also has Windows 7 Ult. x64 on it but I want to use it for storage. I have been trying to boot from CD so that I can delete my old OS partition, but booting from CD just takes me to my new install. Yes, I have changed the boot order but it still boots me to my new install on the new HDD. I have done this before - two WinXP installs on two HDDs - but this time I want to recycle my old HDD. Why can I not get to the CD boot screen that will allow me to partition and format my HDDs? Is it because Windows sees two complete versions of itself? Is there another way to achieve format on my old HDD? I know it is small but I need it until I buy another larger HDD for an archive disk. (I actually have three HDDs. I am trying to do away with my antique IDE drive that I have been using for an archive and now have patched in to my recently purchased Motherboard. I need to use my old ATA to replace it temporarily and just want to clean it off.)

Hi Bill in WA, Welcome to SF

Start>type diskmgmt.msc>enter

This page will show disk configuration and allow you delete/create partitions
Just be aware that if you installed new win setup with old drive connected your boot info may still be on old disk and if you delete it it may leave system unbootable and in need of startup repair
Dont know if your familiar with this, if your not sure post a snip of your maximised disk management and we can advise

Sorry for the obvious question, but have you confirmed that the CD still boots? Asking because CDs do wear out and if its no longer bootable, the PC will go to the hard drive.

If it's not bootable, you should download and burn a CD of the Minitool Partition Wizard Boot CD. You could then boot from that and use it to wipe/erase the partitions.

Thanks for the quick response Pauly. As I look at Disk Management it shows me "boot" only on the new, large HDD. I have deleted as much as I could trying to get my Windows 7 disk to see a problem on the old drive, but it hasn't helped. I actually did disconnect the old drive to set up the new one, it was the only way I could get to the CD screen to let me set up the partition. This morning the old drive was marked as active but the new one was not, however the only options Disk Management is giving me where partitions are concerned is to mark the new, large HDD as active, which I have done hoping it would change something. It did not. Am I missing something on Disk Management?

At any rate, I have attached a snip of Disk Management screen.

One other thing, at startup I am asked to select which Windows 7 I want to boot, but when I pick the old one it no longer boots up. If I disconnect the new large drive and then boot from CD should it now take me to the partition prompt screen (for lack of better term) since the boot is no longer listed on the old drive? If I can get to that screen I can do what I want to do. I am tempted to try it now but have to get ready for work at the moment.

Mark, it is the same CD that I used the day before yesterday to load the new, large HDD, so unless something happened in the last 48 hours... The DVD drive is also very new as is the Motherboard, CPU, and the video card. In the process of a major overhaul/upgrade in preparation to move to Thailand. But it was a good thought.

The partition program is a good thought too. Will try that tonight when I get home from work. Funny I had been remembering the old Partition Magic from the Win98 days - I still even have it, somewhere - but am pretty sure it will no longer work. Your suggestion may just be the ticket for me.

Mark, thank you. I downloaded the program and it worked and very quickly and easily too. It didn't even make me boot to do it. It let me do it from my new install of Windows 7. Thanks very much. And Happy Holidays to all.