IBM is developing a new deep-sleep mode for its Power processors that will allow them to draw almost no power when they are idle, an IBM engineer said at the Hot Chips conference on Monday.IBM's Power7 chips already have three sleep modes that it calls nap, sleep and heavy sleep, and which are implemented based on factors such as the type of workload being run and how much latency an application can tolerate before the processor comes back to life.Latency is a trade-off with each sleep state. The nap mode cuts the voltage to a processor core by 15 percent and can bring it back to life almost immediately. Heavy sleep mode cuts the power to all eight cores by 85 percent, but requires 2 milliseconds to bring the chip back to life.