Updating iPhone On Different Laptop?

[Epicnessx]

So my one laptop does not have enough space to update my iPhone 4.

Is it possible to update it on my other one?
I just do not want my phone and stuff on it completely erased
Would doing a backup before save everything? If not what else could I do?

 

[Applejuiced]

Yes, you can update on another computer and then sync anything you want back with the old computer.
You cant do an OTA update? What phone and firmware version are you on?