How to put an iphone on a new computer?

Right now my if i want to put music on my iphone I need to plug it into my laptop and download music from there. The laptop is getting really old its now 5 years old and slow and it freezes all the time. I have tried many times to get it to only work on my desktop computer. But it won't make the desktop the main computer.

I really want to switch it because everytime I plug my iphone into the laptop the laptop freezes and take 5 years to load.

I also fear that one day the laptop will die an ill be screwed.

Is there any way to change it to a different computer or do I have to buy a new iphone.
I could really care less if it deletes everything off my phone as long it gets o n a new computer.

Try www.howtoidevice.com, they might have a fix for your problem…