diff --git a/Components/8272/i8272.cpp b/Components/8272/i8272.cpp
index 96b50e73e..926879f1d 100644
--- a/Components/8272/i8272.cpp
+++ b/Components/8272/i8272.cpp
@@ -91,6 +91,8 @@ i8272::i8272(BusHandler &bus_handler, Cycles clock_rate, int clock_rate_multipli
 void i8272::run_for(Cycles cycles) {
 	Storage::Disk::MFMController::run_for(cycles);
 
+	if(is_sleeping_) return;
+
 	// check for an expired timer
 	if(delay_time_ > 0) {
 		if(cycles.as_int() >= delay_time_) {
@@ -103,6 +105,7 @@ void i8272::run_for(Cycles cycles) {
 
 	// update seek status of any drives presently seeking
 	if(drives_seeking_) {
+		int drives_left = drives_seeking_;
 		for(int c = 0; c < 4; c++) {
 			if(drives_[c].phase == Drive::Seeking) {
 				drives_[c].step_rate_counter += cycles.as_int();
@@ -122,6 +125,9 @@ void i8272::run_for(Cycles cycles) {
 						break;
 					}
 				}
+
+				drives_left--;
+				if(!drives_left) break;
 			}
 		}
 	}
@@ -146,6 +152,8 @@ void i8272::run_for(Cycles cycles) {
 			}
 		}
 	}
+
+	is_sleeping_ = !delay_time_ && !drives_seeking_ && !head_timers_running_;
 }
 
 void i8272::set_register(int address, uint8_t value) {
@@ -190,7 +198,7 @@ void i8272::set_disk(std::shared_ptr<Storage::Disk::Disk> disk, int drive) {
 
 #define MS_TO_CYCLES(x)			x * 8000
 #define WAIT_FOR_EVENT(mask)	resume_point_ = __LINE__; interesting_event_mask_ = (int)mask; return; case __LINE__:
-#define WAIT_FOR_TIME(ms)		resume_point_ = __LINE__; interesting_event_mask_ = (int)Event8272::Timer; delay_time_ = MS_TO_CYCLES(ms); case __LINE__: if(delay_time_) return;
+#define WAIT_FOR_TIME(ms)		resume_point_ = __LINE__; interesting_event_mask_ = (int)Event8272::Timer; delay_time_ = MS_TO_CYCLES(ms); is_sleeping_ = false; case __LINE__: if(delay_time_) return;
 
 #define PASTE(x, y) x##y
 #define CONCAT(x, y) PASTE(x, y)
@@ -248,6 +256,7 @@ void i8272::set_disk(std::shared_ptr<Storage::Disk::Disk> disk, int drive) {
 	if(drives_[active_drive_].head_is_loaded[active_head_]) {\
 		if(drives_[active_drive_].head_unload_delay[active_head_] == 0) {	\
 			head_timers_running_++;	\
+			is_sleeping_ = false;	\
 		}	\
 		drives_[active_drive_].head_unload_delay[active_head_] = MS_TO_CYCLES(head_unload_time_);\
 	}
@@ -701,6 +710,7 @@ void i8272::posit_event(int event_type) {
 				// Increment the seeking count if this drive wasn't already seeking.
 				if(drives_[drive].phase != Drive::Seeking) {
 					drives_seeking_++;
+					is_sleeping_ = false;
 				}
 
 				// Set currently seeking, with a step to occur right now (yes, it sounds like jamming these
diff --git a/Components/8272/i8272.hpp b/Components/8272/i8272.hpp
index 62ff35db9..9c216aa7c 100644
--- a/Components/8272/i8272.hpp
+++ b/Components/8272/i8272.hpp
@@ -128,6 +128,8 @@ class i8272: public Storage::Disk::MFMController {
 		// Internal registers.
 		uint8_t cylinder_, head_, sector_, size_;
 
+		// Master switch on not performing any work.
+		bool is_sleeping_;
 };
 
 }