Computer strength vs time.

Does the time limit affect the strength of the computers, for example, would the computer in a 15/0 game be stronger than 1/0? NOTE: I mean the same level of computer (Computer-1-easy etc.)

Initially computers rely on their "opening books". Then they start computing variations. The longer time they have to "think", the stronger their move will be.

Thanks, so the time is calculated for 'dumbed down' computers.

At the level computers are at now, the rule of thumb is that doubling a computers speed will make it around 50-60 ELO better. It's not exact. Some people say it's 70 ELO. The exact number is probably different for each chess engine. Doubling the speed is equivalent to doubling the time on the clock.

Thanks