Can I sync my iPhone 6 to my old computer without losing everything?

Today, I got on my old desktop computer to see what pictures and music I had on there. I have a laptop, and on that laptop, I have different music in my iTunes library. I was feeling nostalgic after looking through my old desktop, and now I'm wanting to sync my new iPhone 6 to my old computer to get my old music on my phone. I've read that you can lose your pictures, apps, and app data that way. The bad thing is, my laptop with all of my newer music and photos backed up on it is completely broken and I have no way of using it at the moment. I mainly just want all of my old music from my other computer on my phone, but I'd rather not lose all of my photos, apps, and phone data. Is there any way I can go about doing this?

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