Figure out exactly how much caffeine you really need pre-training.
In a recent study featured in The Journal of the International Society of Sports Nutrition, researchers concluded that 3mg of caffeine per kg of body weight was needed to significantly increase squat and bench press maximal power. To put things in perspective, that is roughly 273mg of caffeine for a 200lb person. Upon a short google search of popular energy drinks, the average caffeine content looks to be about 150mg / 16oz can. An 8oz cup of brewed coffee yields roughly 90-100mg of caffeine.