Make sure mode is set to Ultra and 1 minute for this achievment. I got it by setting the speed to 9 and tried to get as many tetries as I could (clearing 4 lines at a time). When it was clear I couldn't get any more, I cleared 1 and 2 lines until the time ran out. Achievment will pop as soon as you get the 5,000 points. I set the speed to 9 because the pieces will fall faster and you will have more pieces to work with. At the lower speeds, you don't get enough pieces to get enough points before the minute is up. Good luck!