Well I’ve just read on the web that the iPhone 3G and 3GS processors are underclocked in order to save the battery life and prevent heat on device. 3G device uses an ARM 620 MHz processor and 3GS an ARM 833 MHz one, respectively underclocked to 400 MHz and 600 MHz.
Would be great to increase it to the processor’s original values. Actually there is one way to do it, I didn’t try that myself but read that there is a step of process to do after Jailbreaking the phone. So you must have it Jaibreaked and following a few steps will fire up your device and make you happier about it’s speed but contrary not with the battery life. Frankly I am already dissappointed with battery life. Apple should give you the choice to roll ARM device to have it original values.
I don’t want to jailbreak mine but for the ones who does, here are the steps to walkthrough.
How to Overclock CPU on iPhone 2G, iPhone 3G, iPhone 3GS, iPod Touch
Step 1. Make sure you have a Jailbroken iPhone/iPod Touch. Jailbreaking Guides
Step 2. Using a SSH tool like Filezilla, Navigate to System/Library/System/System Configuration/PowerManagement.bundle/
Step 3. Rename file “com.apple.SystemPowerProfileDefault.plist” to “SystemPowerProfileDefaultbak.plist” or something that device doesn’t recognize.
Step 4. Reboot, and your iPhone/iPod Touch would Run on native Processor clocks.
Important: Increasing the clock speed would degrade the CPU’s lifespan by several minutes. However, since the device is not designed to handle the heat generated at higher clocks, we recommend you to terminate apps if device appears to overheat. Also checkout tips to Prevent Overheating of iPhone
Thanks to Taranfx for sharing the steps above with us.