Motherboards with integrated components, such as sound cards and modems, are generally cheaper overall than motherboards that would need those components purchased separately. If I was building, for example, a desktop gaming PC, I would use a non-integrated motherboard so that I could choose the appropriate components that would meet my specific needs. Such a system is expensive to purchase already built so I would save money by building a bespoke rig. However, if budget was a consideration, using an integrated motherboard saves time and money. Ultimately, I would have to weigh the cost of the initial build against the cost of wanted and/or need upgrades in the immediate and long term future.
I wouldn’t consider replacing a motherboard on a laptop. The current costs of laptops doesn’t make replacing the motherboard cost effective. I would likely trade in the older laptop for a newer model.
If I had no choice in the matter, I would check to see if the unit is under manufacturer warranty for possible replacement, consider upgrading the RAM (if possible), or restoring the computer to factory defaults.