Question is answered several times before here.
Yes, you can run more than one xampp on the same computer.
But if you want to start two apache (or other modules) the same time, you had to change their ports.
If you don't use them the same time, thats no problem.
Just download the zip version of xampp 1.7.3, unzip it (e.g. in the path c:\xampp173\), run the setup_xampp.bat script and thats it.
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