Google launched "Enhanced CPC," a new automated bidding feature that can help you improve your ROI on your campaigns with manual bidding. "Enhanced CPC uses your campaign's historical conversion tracking data to automatically adjust your Max CPC bid based on the likelihood that your ad will convert. As a result, you should receive more conversions while maintaining or reducing your overall CPA and hopefully spend less time managing your Max CPC bids," informs Google.
To use Enhanced CPC, first enable (if not already using it) Conversion Tracking for your campaigns. Then, simply navigate to the 'Bidding and Budgeting' section of settings tab for your campaign, and select the checkbox under 'Enhanced CPC.' Please note; campaigns using Enhanced CPC cann't currently be modified using AdWords Editor.