Being that this is a DRIVER_IRQL and not just a IRQL then I would say that the problem with this is a driver issue. Did you change any drivers/install new hardware recently?
According to
Technibble.com, this error means:
Stop 0×000000D1: DRIVER_IRQL_NOT_LESS_OR_EQUAL - This Windows stop error indicates that the computer tried to access memory using a kernal process which had a IRQL that was too high (as kernal processes can only access IRQLs that it is either equal to or IRQLs that less than it). This is usually caused by incorrect or incompatible drivers.
Hope it helps.