Actually you can make it legal by putting the old hard drive in the new machine. You see, what sonstitutes a "new machine" is not clearly defined. You could replace every part in your HP and it would still be considered the original machine. But if you DROP your completely original HP and wreck the case, you can put it into a new case and it's still the "original machine". And of course, if you put your old pre-loaded Dell hard drive in a new machine, you are not required to format the drive, you can use it as is, and fix the configuration in Device Manager! So now, say the following happens:
1.) Your Dell fries a hard drive. You put in a new one. It's now a "Dell" hard drive for the purposes of licensing.
2.) Later, you fry your board. You now need a new board. but you can't afford a Dell board, so you buy an ATX board, case, and power supply. You transfer the other hardware, so it's still the licenced machine.
3.) One by one, the other parts die and are replaced. Since one single part doesn't disqualify the machine, your licence is in tact. But soon, you find you have NOT ONE original Dell part in the machine!
OK, here's another (less extreme) example: You want to upgrade your HP. You buy a standard replacement board. Now, the HP restore disk no longer works! But because it's the same machine except for the board, you still have the license. What to do? Borrow a copy of an original Windows OEM CD, and use your original license! After all, the license is for that machine!
Look at Gateway towers: They are standard ATX. You can put any board you want in them. The license in most situations is a sticker ON the CASE! Put any hardware you want in there, the license is still valid, but the restore CD will no longer work once you replace the board! So you are forced to borrow a standard Windows OEM CD!
<font color=blue>Watts mean squat if you don't have quality!</font color=blue>