Can I Dual Boot windows 7 x64 and windows 7 x86? I have window 7 x64 on my main HDD. Can i instal x32 on my other HDD?

Hi

You must install different windows versions to different hard drive partitions

The booted windows partition will be c: when windows active

It is likely the boot manager will be on the exiting hard disk so if this failed the other hard drive would not be bootable until a emergency repair has been made

To keep every thing separate you need to remove existing hard drive and install windows on remaining hard drive
Then refit old hard drive

Actually no need to physically remove hard drive only disconnect sata data & power cables

You would also need a bios which lets you choose boot hard drive at bios startup
Often F12 or F8

Regards
Mike Barnes