Need help in choosing a laptop

I can’t decide which one of these laptops is better, they are all at the same price so the price is not the issue the model number here is the issue
Dell Inspiron 15R N5520
Intel� Core� i5-3210M Processor (3M Cache, 3.10 GHz)
4GB DDR3 RAM
1TB SATA 5400 rpm
DVD+/-RW Double Layer drive
15.6″ High Definition (720p) LED Display with Truelife (1366 x 768 Pixels)
AMD Radeon� HD 7670M DDR3 1GB
webcam with digital microphone
WLan – Bluetooth – USB – 10/100 ethernet
(3) USB 3.0 + (1) USB 3.0 PowerShare
HDMI – D-sub
8-in-1 Media Card Reader
6-cell 48WHr Li-Ion Battery
Dell Inspiron 15R 3537
Intel� Core� i5-4200U Processor (3M Cache, up to 2.60 GHz)
4GB DDR3 RAM
1TB SATA 5400 rpm
DVD+/-RW Double Layer drive
15.6″ High Definition (720p) LED Display with Truelife (1366 x 768 Pixels)
AMD Radeon� HD 8670M DDR3 1GB
webcam with digital microphone
WLan – Bluetooth – 2 x USB 2.0 – 2 x USB 3.0 – 10/100 ethernet
1 x HDMI 6-cell 48WHr Li-Ion Battery
Dell Inspiron 15R 5537
Intel� Core� i5-4200U Processor (3M Cache, up to 2.60 GHz)
4GB DDR3 RAM 1600MHz
1TB SATA 5400 rpm
Tray-loading DVD+/-RW
15.6″ HD LED Display with Truelife (1366 x 768 Pixels)
AMD Radeon HD8650M DDR3 with 2GB 1.0MP Webcam with digital microphone
Wi-Fi – Bluetooth 4.0 – USB – Ethernet
HDMI
6-cell Li-Ion Battery
Dell Inspiron 15R N3521
Intel� Core� i5-3317U Processor (3M Cache, up to 2.60 GHz)
4GB DDR3 RAM
1TB SATA 5400 rpm
DVD+/-RW Double Layer drive
15.6″ High Definition (720p) LED Display with Truelife (1366 x 768 Pixels)
AMD Radeon�
webcam with digital microphone
WiFi – Bluetooth – USB – Ethernet 10/100
HDMI
Touchpad
Memory card reader
6-cell 48WHr Li-Ion Battery
Dell Inspiron 15R N5521
Intel� Core� i5-3317U Processor (3M Cache, up to 2.60 GHz)
4GB DDR3 RAM
1TB SATA 5400 rpm
DVD+/-RW Double Layer drive
15.6″ High Definition (720p) LED Display with Truelife (1366 x 768 Pixels)
AMD Radeon� HD 8750M DDR3 2GB
Webcam
WLan – Bluetooth – USB – 10/100 ethernet
(3) USB 3.0 + (1) USB 3.0 PowerShare
HDMI – D-sub
8-in-1 Media Card Reader
6-cell 48WHr Li-Ion Battery
So which one should i go for it ?
Answer #1
CPU Performance wise: i5-3210M>i5-4200U>i5-3317U
GPU Performance wise: HD 8750M>HD 8670M>HD8650M>HD 7670M
When buying a computer for gaming purposes, The performance of the video card is always more important than the CPUs, Keeping this mind, I suggest you go with the last one. Also, It’d probably be a good idea to add it an additional 4 gigs of RAM.
Answer #2
Lenovo Y580.