If you always clean dust on the vents and don't simply OC your laptop, it should be able to last for 4 years easily. Especially for models NP8130 onwards which have 2 vents.

Built quality has no problem at all, these Sager models has launched more than half year.
i5 is suitable for gaming, since gaming doesn't necessary need 4 cores. i7 is suitable for programming, designing and multi-tasking purpose.
Heat: i7>i5. However, there is no heat problem on the machine you mentioned, but NP8 series cooling design is better though.

Gaming go for i5, Multi-tasking go for i7.
NP5165 cannot last for 4-5 hours, but it can last for 2.5 to 3 hours, it depends on the brightness of screen and your usage, i5 has less power consumption.

Well for the terms of gaming, as you would know current games most are using 2 cores out of 4 cores, or even like 970 and 990 options as a 6 core CPU. Some of few games over market are managed to take advantages of all the QUAD CORE CPUs, even though that would not be bad to tell you difference of a i5 and i7 with a GTX 560M in a game such as DIRT 3 in FPS would be like 1 to 5 FPS difference !!!! well Core i7 is much suitable for purpose of a heavy multi tasking which would be quiet dependent on which CPU u might use (2620QM, 2720QM, 2820QM or 2920XM)  - there will not be any heat problem if you are going with core i7 sandy-bridge which are producing less heat and using less power consumption as well.
Well for your propose i am recommednign you core i7 2720QM to up

For gaming, you won't feel the different, for multi-tasking, there is significant different, i7 2720qm is a very powerful CPU, but if you cannot fully utilize it, no point also.

well the difference between these core i7 CPUs are mostly on having a higher clock however they are with locked multipliers, plus the core ratio of each model is higher as the number says, like 2630QM core ratio is 26 and Core ratio of 2820QM is 28 , the highest clock is for Extrem editions with unlocked miltipliers, moreclock speed and having more Cache size (based on CPU model) will provide us a better multi tasking and speed when some heavy apps are fuctioning together.....thats the difference, i am personally recomendng 2820QM or 2920XM if u are working with some heavy apps such as 3D max, Auto-Cad and so on, will have a faster loading and action specially if laptop have a SSD

then dont forget to get some RAM also ! i mean dun buy with 4GB ! i have 12 GB ram however its useless cuz i close many things most of the time, but if u leave many thigs open and want to play game also, a good cpu plus enough ram might help you much, i am suggesting to u that u can get a SSD as well to load everything faster than usual

in terms of working as engineer and if U do need it, i mean as i explained before having 2920XM even wont help that much to your FPS in games unless U jUst WaNnA HaVe It For The NaMe of EXTREME EDITION and Fun - for me if i have the funds i 'll get 990X ! like cyz the lable is awesome   ! haha...but it think it would WORTH if u prefer a heavvyy multi tasking...you might not understand the difference yourself between these range of 2630 to up but i would give a better loading and speed when there many apps  left open and running,-- now i have a core i7 970 six Core and sometimes i really can feel that the laptop is very nice ! sometimes i am converting a HD movie from camera while i am browsing, there is no lag over my laptop  - so if u dun have problem with your procket then i guess u can easily go with it and be happi - 2720QM to up (2820 and 2920) are really great investments.
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yep once u got the funds a SSD would by really fun ! i can really feel how fast my np7282 is boot up and shitdown or run the apps which are installed in SSD, i was thinking to get for my third storage a 300GB SSD also...its a realy BooosSStt

No, NP8130 don't have optimus.

Why complicate?

To be frank, NP8130 (8 cell, no optimus) has similar battery life with NP5165 (6 cell, optimus).

i have a question....2 gb ddr3 performance better or 1.5gb dd5?

Sager NP8130 / Clevo P151HM1
- 3% Cash Discount, 8GB RAM Promotion & Price Match! Ask us about our Current Specials! We GUARANTEE we have the lowest price for the same configuration!
- 15.6” FHD 16:9 LED Backlit Wide screen (1920x1080) Super Clear Matte Type Screen
- Standard Dead Pixel Policy
- - 2nd Generation Intel® Core™ i7-2630QM, 2.0-2.8GHz, (32nm, 6MB L3 cache)
- - IC Diamond Thermal Compound - CPU + GPU
- nVidia GeForce GTX 560M 1,536MB PCI-Express GDDR5 DX11
- No Video Adapter
- ~ 8,192MB DDR3 1333MHz Dual Channel Memory (2 SODIMMS)
- Standard Finish
- ~ 750GB 7200RPM (Serial-ATA II 300 - 16MB Cache)-
- ~ Combo Dual Layer SuperMulti DVDRW/CDRW Drive w/ Software (When selecting a Hard Drive in the Optical Bay, No Optical Drive is Included)
- No Extra Optical Bay Hard Drive Caddy
- No Back Up Hard Drive
- NO External USB Optical Drive
- No Floppy Drive
- Internal 7-in-1 Card Reader (MS/MS Pro/MS Duo/MS Pro Duo/SD/Mini-SD/MMC/RS)
- No Back Up Software
- None Standard--
- Intel® Advanced-N 6230 - 802.11A/B/G/N Wireless LAN Module + Bluetooth
- No Network Accessory
- Built in 2.0 Megapixel Camera
- No TV Tuner
- Sound Blaster Compatible 3D Audio - Included
- No Carrying Case
- Smart Li-ion Battery (8-Cell)
- No Car Adapter
- None Standard*
- No Dock/Hub/Adapter
- Integrated Fingerprint Reader
- No External Keyboard or Mouse
- No Notebook Cooler
- No Thanks, Please do not Overclock my system (Overclocking will add 3-6 business days to build time)
- No Operating System Standard - Drivers & Utility Software Only
- No Office Software
- No Software Bundle
- 3 Year Labor* 1 Year Parts Warranty Lifetime -24/7 DOMESTIC Based- Toll Free Telephone Tech Support (Labor Warranty through Xotic PC)
Includes FREE Shipping Both Ways for Warranty Repairs
- No Xotic PC Gear

Get the NTSC 95% color gamut screen if screen is important for you.

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jackytiao (NP8130)
k-nen (NP8130)
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Kelvin (NP8150)

to become Sager owners!