Most wood floor manufacturers specify plywood or OSB subfloors not less than 3/4″ thick on 16″ OC joists. This avoids excessive deflection and provides a good attachment surface. When I moved into my current house there was an engineered wood floor glued on a 5/8 particleboard underlayment on 1″ T&G plywood subfloors. Those floors did not seem to have much problem other than finish. I removed the underlayment and finish floor and put a new 3/4″ wood floor on a 1/2 inch plywood underlayment on the 1: subfloor.
I would go with a minimum 1/2″ plywood underlayment on your 5/8 particle board subfloor attached with 1-1/2″ ring shank nails and underlayment glue to the subfloor. The additional thickness will allow a nailed floor and will compensate for deflection problems in the particleboard. 1/4″ plywood will give a smooth underlayment surface, but will not add the structural rigidity that would avoid floor creaking. If you can manage the extra thickness, it would probably be a better installation.
