How are you able to validate browser compatibility of a particular website? say test on IE6/IE7 when you only have a single computer. Sorry, if im asking a stupid question.

 

Also, it would be nice if you can give me advice on how to check it on all most common browsers.

 

heers.

The best way is to download the most used IE.FF.Opera.Safari.etc locally and check compatibility there. Then http://browsershots.org/ will be a resource you will use too. Im sure there are plenty more too

Funnily enough, I'm doing that very thing

 

I'm using a website http://browsershots.org/ to very that a page is ok in a number of browsers

 

It does a huge number of browsers, but beware, it does take a while to run through them all