I'd think the two issues could probably be related. Snoring could be a sign of sleep apnea (even mild) which could be preventing you from getting restful sleep, even though you're length of sleep is adequate. That could ultimately be the reason you're feeling lethargic throughout the day.
I tend to gain a lot of water and bloat on dbol. If you've put on some size and added some water, that could be causing the snoring/possible sleep apnea type of symptoms.