RAID 1 - What happens if drive fails?

Planning a fault-tolerant system with RAID 1 using 2 drives, X99 motherboard, Windows 8.1. I understand if one of the drives fails, system will continue uninterrupted with the other drive. But how does the system inform me that mirroring is no longer being performed and that a drive needs to be replaced? Thanks for the help.

If you are using the on-board RAID, then you should be running the Intel Rapid Storage software. When a drive fails, you will get a popup in the notification area of Windows.

Great. Thanks so much!