Apple Notebooks Take Huge Performance Hit without Battery

Some notebook users pop them out when their systems are running on AC with hopes of extending the life of their battery by a few months.

While I was benchmarking third-party RAM with a MacBook Pro this week, I noticed that the computer was taking a huge hit in performance when it wasn't running on Apple-supplied memory. A minor decrease in performance might be unlikely, but a 37 percent plunge in processing power seemed impossible. After some backtracking, I realized that I had been running the benchmarks without the battery installed after I'd swapped out the stock RAM for third-party memory. The MacBook Pro was running off AC power for both tests, but the battery was installed only while I was running the benchmark with 4GB of stock RAM.

After some digging, I found that the performance drop is documented on Apple's support Web site--though honestly, Apple's reason for forcing a drop in processor speed doesn't make a whole lot of sense. Apple justifies the speed reduction by explaining that it "prevents the computer from shutting down if it demands more power than the A/C adapter alone can provide." But what happens when a battery is no longer able to hold a charge? Does the processor speed drop in that case as well?

We benchmarked our 2.53-Ghz MacBook Pro with 4GB of RAM using Cinebench R10's multiprocessor test, and achieved a score of 5,549 with the battery present and 3,504 with the battery removed.

Lesson learned: The battery stays in. If you're a MacBook or MacBook Pro owner, you'll get the best performance out of your system when you leave the battery in. A small extension of your battery's life span is not worth a 37 percent drop in performance.(www.gearlog.com)