At this budget the best option is Acer 5740G-6979. It offers not only the best configuration but also one of the best battery life compared to the laptops from other brand in the same range.
Specification
Operating System Windows 7 Home Premium 64-bit
CPU Type Intel Core i5-430M(2.26GHz) 2.53 GHz turbo Boost
Screen 15.6"
Memory Size 4GB 1066 MHz DDR3 (upto 8 GB support)
Hard Disk 500GB 5400 rpm SATA
Optical Drive DVD Super Multi
Graphics Card ATI Mobility Radeon HD 5650 1 GB GDDR3 DirectX11
Video Memory 1GB DDR3 VRAM
Communication Modem, Gigabit LAN and WLAN
Battery Life 3.0 hours
Dimensions 15.10" x 9.90" x 1.03" - 1.50"
Weight 6.16 lbs
Display: 15.6" 1366X768 with LED back light & Acer Technology
Audio: True 5.1 Channel Surround Sound Output
3rd Generation Dolby Home Theater Audio Enhancement, featuring Dolby Digital Live, Dolby Pro Logic IIx, Dolby Headphone, Dolby Natural Bass, Dolby Sound Space Expander, Dolby Audio Optimization, Dolby High Frequency Enhancer Technologies
High Definition Audio Support
Built-in Microphone
This is the best performance laptop in this budget. If you go for Sony or dell, you will get Core i3 and HD 5470/5450 graphics card which are just good for watching movies. don't event think of playing new games on it. AnandTEch also reviewed it and said it is one of the top products.
