OK. I thught it was posible to move the programs on a seperate drive and somhow backup the registry so that i could still use it. But is there a big dif in preformence of W7 when i update vs clean install?
I would always recommend a clean install over an upgrade. Of course, you can always just upgrade and see how it goes. That won't take you too much time to do. Then, if you notice things a bit laggy or slow, then do the clean install - which of course is more involved.
My general suggestion if you are changing OS is to use a partition backup program like Acronis True Image or others like it.
1. Do a clean install of the new OS and let it update whatever it needs.
2. Install the backup program (e.g. Acronis) and make a backup of the clean install
3. Install all drivers
4. Make an incremental backup (i.e. it will only contain changes since the last backup)
5. Install all programs
6. Make an incremental backup after that.
That way, if you ever run into problems, you can decide to go back either to the fresh install state, or the "with installed drivers" state, or the "with installed programs" state.
And if your hard drive dies one day, you'll have the new hard drive with everything installed in a matter of 30-40 minutes (assuming your backup files are not on the dead hard drive

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