Old computer broke, can I decommission the product key?

So I had a computer with Windows 7 installed on it. Unfortunately, it broke beyond repair, and I was forced to "decommission" the computer to my garage where it sits now. Now I have a new computer, but I realized that I only have one product key for Windows 7. That key is used on the broken computer, while I can't activate Windows 7 on my new computer because the product key is already in use.

Is it possible to somehow free up the product key again? I know that you can somehow uninstall the OS on an old computer to free the key up, but I have no way of uninstalling it when the computer itself won't start up. Is there another way to free the product key up, or am I now forced to either fix the computer or buy another copy of Windows 7?

A migrated retail Product Key is freed up after reinstall during the required activation robocall, when you answer the question "How many computers is this copy of Windows 7 installed upon" with the only acceptable answer "One".

This authorizes MS to overwrite in their Activation servers the hardware ID associated with a retail Product Key with a new one represented by the number string traded during the call.

If for any reason the old PC is started up again, or its HD is used elsewhere, be sure to wipe the HD or delete the partition since the old OS will lose activation if connected to the web anyway.