The disclosed embodiments provide a system that drives a display from a computer system. During operation, the system writes graphical output to protected memory and drives the display from the protected memory. If the graphical output lacks protection, the system discontinues the driving of the display from the protected memory. In particular, upon detecting a lack of protection in the graphical output, the system continues to drive the display from the protected memory during a grace period associated with the lack of protection in the graphical output. The system then discontinues driving of the display from the protected memory if protection of the graphical output does not resume during the grace period.

Techniques for operating a receiver are provided. An example method according to these techniques includes receiving a content type indicator from a transmitter indicating that a content stream from the transmitter comprises a first content type, performing a first integrity check on the content stream by decrypting content from the content stream based in part on the content type indicator, incrementing a counter responsive to the first integrity check failing due to a mismatch between the content type indicator and the content of the content stream, performing a second integrity check on the content stream by decrypting the content from the content stream based in part on a second content type responsive to the counter exceeding a threshold, and decrypting the content stream based in part on the second integrity check being successful.