Yes indeed. Chips and other circuitry powered by current leakage paths through protection diodes and through improperly biased voltage rails on multi rail parts can lead to some very strange problems. The worst case is when a system has a standby supply with an improper design and some current leakage path triggers a latent PNPN junction stack on a chip. Later when the main power rail comes on there can be a POW and the device is asked to let out its magic smoke and be reduced to white ash.

I actually had a DELL desktop computer that expired in this manner. At the end of one work day the computer was put into its hibernate mode whilst some test circuitry hooked up to a USB port was left powered. The next morning when entering the office and turning on the computer there was a thrack sound and the computer would not boot. Later inspection reveaked a small 2-3 mm hole in the main motherboard chipset component that had a white powder coming out of it.

Michael Karas