I've started a 5x5 plan. Train about 3-4 times per week and split the big lifts squats, deads, bench press, dips, miltary press and chins over the days and add some accessory groups in around that. I've made good steady progress at this.

Previously, I did the standard pyramid system but never seem to advance much   cause I destroy myself on the first couple of sets then have zero in the tank for the last few, therefore, never seem to push my PB.

How can you produce good sets late when you burst yourself on the earlier sets. I'll go 12 reps 30k, 10reps 35k, 8 reps 37.5, then do something poor on 40k. However, I'm benching over 40k on the 5x5 plan. Why is pyramiding not working?