confused about buying new laptop

[Ryuregan]

im confused choosing between two laptops,i want it for gaming and some engineering stuff,all laptops over here dunn't even come close to these two so i think i narrowed my choice circle to these two

Alienware Klipsch Edition M17x R4 3rd i7 3840 QM

*Processor: Intel® 3rd Generation CoreTM i7-3840QM 8MB Intel Smart Cache 2.80GHz - 3.80GHz with Turbo Mode ..

*2x Hard drives 1 TB HDD + 128 SSD sata 3

*Display : 17.3" FHD (1920x1080) LED backlit LCD (Glossy Type) ..

*Ram : 16GB DDR3 1600 MHz (4 x 4GB) System Memory - 4 Memory Slots ..

*GPU: 2GB GDDR5 NVIDIA® GeForce® GTX 675M ..

*sound system : Creative Sound Blaster Recon3Di High-Definition 5.1 Audio with THX TruStudio Pro Software


Alienware M17x R4


Processor:
Intel Core i7-3610QM 2.3 GHz (Intel Core i7)
Graphics adapter:
AMD Radeon HD 7970M - 2048 MB, Core: 850 MHz, Memory: 1200 MHz, GDDR5, 8.934.2.0
Memory:
16384 MB, 4x 4096 MB SO-DIMM DDR3-SDRAM PC3-12800 (1600 MHz), 4 slots, max. 32 GB
Display:
17.3 inch 16:9, 1,280×720 pixel
Mainboard:
Intel HM77 (Panther Point)
Hard disk:
Samsung SSD 32 GB + Seagate Momentus 7200.4 (ST9500423AS), 500 GB, 7200 rpm
Soundcard:
Creative Sound Blaster Recon3Di @ Intel Panther Point PCH-High Definition Audio Controller
Connections:
1 USB 2.0, 4 USB 3.0, 1 VGA, 1 HDMI, 1 DisplayPort, 1 Kensington Lock, 1 eSata, Audio Connections: 1 Line-In, 3 Line-Out (incl. S/PDIF), Card Reader: 9-in-1, 1 HDMI-In
Networking:
Atheros AR8151 PCI-E Gigabit Ethernet Controller (NDIS 6.20) (10MBit), Intel Centrino Wireless-N 2230 (b g n ), 4.0 Bluetooth

that two alienware laptops are used,so i wanna k what to look at when buying and how to check them
thanks in advance

 

[RektSkrubs]

The Alienware M17x R4 has better specs for the price.

 

[Ryuregan]

actually both r alienware m17x r4!!
and do u k what to check for like problems or issues as im new to laptops been with desktop my whole life