Eris its not power...I run mine fine on 12V.
If your getting trails at 3 seconds in tracking...I guess you mean it's unguided and you get star trails! If it's unguided and trails then the alignment must be off.
Normally DEC shouldn't be doing much when guiding if it is then the alignment is not right. You said without guiding it drifted off....its gotta be alignment.
Clutches should be tight but enough to allow slip if bumped.
You might want to check your Gemini settings and divisors are correct.
Use Gemini ASCOM, it makes this easy. If they are correct can you change your divisor to speed up the Ra?
The only other thing is its slow in Ra....although lets not go there yet!