Triple boot installation XP 7 XP

I'm currently running a dual boot on my Desktop, XP and 7-64. Both are set up for office work. Typical personal information etc. I would like to also use it as a gaming computer, but have heard so many horror stories about DRM/Steam software (vulnerabilities and other unsavory effects), I'm afraid to use the system for gaming. However, I thought installing a third hard drive (current dual boot uses dedicated drive for each os) with another copy of XP would provide enough isolation to to mitigate most risk. So, that's my goal.

I have several questions pertaining to this set up.

1) Both current installations are legally licensed. Can I have 2 XP installations from the same installation disk or would I need to purchase a separate license?

2) I've read that if dual booting, the older OS must be installed first or else the system could be rendered useless. Since I want to add XP as the third boot OS, will that be a problem? Since 7-64 is also installed?

3) The desktop in question is a workstation with a Quadro card for heavy CAD/modelling work. It runs pretty hot. I would like to be able to turn off the hard drives not being used. Is there a way to do that? Power management? If necessary, I'm not opposed to installing hardware switches to disconnect them. Every hear of anyone doing this? Is it enough to simply disconnect the power to the drive or will that cause errors?

Any input would be greatly appreciated.

Installing in SATA AHCI mode allows hot-switching which can Safely Remove a HD from the System Tray.
You could then disable in Device Manager.

With multiple HD's each containing an OS, the best way to multi-boot is to select the HD to boot from BIOS Boot Menu key, not use Windows Boot Manager. This is achieved by removing all other HD's during install which should be done anyway. If you'd like to reconfigure the extant OS/HD's for this post back a screenshot of Disk Management - Post a Screen Capture Image .

Overheating is dealt with in Troubleshooting Steps for Windows 7

Installing in SATA AHCI mode allows hot-switching which can Safely Remove a HD from the System Tray.
You could then disable in Device Manager.

I'm trying to do this with what I have, if possible. I don't believe all three drives are SATA. I'm assuming "hot-switching" means "with the computer powered up." What problems could I expect if I simply had manual toggle switches installed? One to kill the power to each drive individually prior to powering up the computer? If I booted from the BIOS, each drive would be seen as C:. Could that damage anything?

With multiple HD's each containing an OS, the best way to multi-boot is to select the HD to boot from BIOS Boot Menu key, not use Windows Boot Manager. This is achieved by removing all other HD's during install which should be done anyway. If you'd like to reconfigure the extant OS/HD's for this post back a screenshot of Disk Management - Post a Screen Capture Image .

I'm just curious. It sounds like you prefer BIOS boot from Windows Boot Manager in general? If so, why?

Overheating is dealt with in Troubleshooting Steps for Windows 7

It's not overheating. The fans kick up to "turbo" when I'm doing anything with heavy graphics, animations etc. Heat kills electronics. Anything I can do to reduce power is good as I see it. Typically, I only use the one drive with 7-64. It just seems inefficient having two idle consuming resources. I realize they aren't in full spin mode, still it has to be contributing to heat.

It is correct for each OS to view itself as C when booted. However XP is too old to know how to configure this so needs to be installed first for this reason.

Booting via BIOS avoids issues which can arise with the Windows Boot Menu. We've come to like it better here after five years experience with these issues. You can try it to see since having each OS HD boot itself is always best, while the Windows Boot Menu can always be added back later if you prefer it and the drives will then still be able to boot independently if needed.

A hardware expert would need to answer your question about toggling HD's via a switch. It only comes close to being done in Windows by Safely Remove in AHCI mode.
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