W7 On Desktop, Can I Install On Laptop (Trial)?

I have W7 installed on my desktop and love it. I have an older HP Pavilion dv7 laptop that had Vista on it that's causing me all kinds of problems since I tried to install XP on it. After a lot of searching around I'm seeing that some of the hardware that HP used on it isn't compatible with XP and that I'd have to do a lot of individual driver hunting to make it work.

Not worth it to me, because I love W7 and would love to upgrade the laptop to it. Problem is, I don't know if I have problems on the laptop beyond the OS. Can I use the same disc to install W7 on my laptop that's installed on my desktop, and just not register it initially? I want to make sure the computer gets up and running well and then I'll purchase a dedicated W7 license for the laptop, but I hate to waste $100+ if there are larger problems with the laptop and I have to end up purchasing a new laptop with W7 on it already. I don't want to try to install it out the laptop though and have it deactivate my desktop.

Thanks a ton for any help.

I thought it was pretty self explanatory. I have a desktop and a laptop. Windows 7 is and has been installed and registered on my desktop for a long while now. You only get one install per copy of W7, correct?

Desktop = W7 installed and registered and I want to keep it that way

Laptop = Vista-installed, tried to switch to XP but a lot of compatibility issues, want to upgrade to W7 but the laptop is having problems that I'm not sure are related to me trying to install XP and driver incompatibilities or if there are hardware issues. I don't have a copy of Vista, only XP and W7. Want to install W7 to make sure it's not hardware issues but don't want to buy a copy of W7 only to find out it is hardware issues and have to replace the laptop with a new one that would have W7 on it anyway.

Thanks Brink, that's exactly what I was looking for. I know it was an easy answer but I couldn't find the info specifically related to my situation. Thanks so much.