Mine hexidecimal is set to 0…Does that mean that the reserve CPU is basically off ?
no,
(decimal) 20 is the default;
registry settings to value lower than 10 evaluates to 10 (decimal) only,
10% is everytimes reserved for system tasks
also remarks:
a)
MMCSS sends a special command to the network stack of the operating system, telling it to throttle network packets during the duration of the media playback. this is because network DPC is hardware interrupt based (higher priority then the user software (user-mode code)).
b) from the microsoft book windows internals revision 7 part 1
MMCSS supports a feature called deadline scheduling. The idea is that an audio-playing program does not always need the highest priority level in its category. If such a program uses buffering (obtaining audio data from disk or network) and then plays the buffer while building the next buffer, deadline scheduling allows a client thread to indicate a time when it must get the high priority level to avoid glitches, but can live with a slightly lower priority (within its category) in the meantime.