Windows 7: SSD install - can I keep OS on current HDD ?

Hi

Installing Windows 7 64 bit to new ssd. The current hdd will still have the current Windows 7 OS on it. As long as I have the bios boot set to the ssd can I leave the other win 7 OS on the mechanical drive in case of problems ?

Will this cause any problems ?

It shouldn't cause problems if you have it configured for dual boot but most of the time it is two different OS

Is there a real reason why you need the same Os on another drive

I would think it would be easier to image the drive if it is small enough to fit on the SSD and use the other HD as the back up for more information you don't have to but if you are looking to boost perfomance i would no doubt just start over best results

clean OS clean drive can't beat that with a baseball bat

Solarstarshines is correct about a clean install. But, you need to disconnect all other hard drives when doing the clean install. This has other reasons, but it also keeps you from dual booting where it asks do you want boot into windows7 or windows7. You can boot into the old hard drive anytime you want by using the one time boot key.

Remember only one activation at a time per Product Key. So you'll likely need to delete the old OS if you use it's Product Key to activate the new install, or just use another key.

Be sure to get everything transferred over if you activate the new OS with the old key - you have 30 days to do so.

He can still keep the OS on the hard drive and not boot to it or activate it can't he? Why would he have to delete the old OS?

Yes, even if the old OS loses activation and is unable to start it can still be used as an inert data partition.

However I lean against keeping intact OS's for storage purposes as they can present boot problems plus derail the System boot files during a Repair if not kept marked Inactive.

If he changes the key to the new OS the old OS may well hold activation since it is on the same hardware, but this cannot be counted upon plus it is not legal under the EULA.

There is a way to delete the OS files off the partition but it requires wrestling System file ownerships so its better to gradually move data off the partition to get rid of the old OS the correct way by deleting or formatting the partition it's on.

Two installs,two Product Keys needed.

Take a look at those Tutorials:
SSD - Install and Transfer the Operating System
SSD Tweaks and Optimizations in Windows 7
SSD Alignment
SSD / HDD : Optimize for Windows Reinstallation