If you multi task or run apps that can use all the I7 threads then it wins.
If not then the I5 wins, better single thread perf.
Graphics.
The hd 4000 vs gt 525m is close to a wash.
The 4000 will use system ram so keep that in mind.
Since I work on computers I am often left with old junkers to get recycled or ones people never pay for and pickup. These are usually deserving of being recycled but sometimes I am left with some nice units.
I have several i5 and i7 units that I use frequently. Some were purchased while others were leave behinds. Many people are sick and tired and just plain frustrated with the old unit by the time they get me to transfer the data to a new one and never want to see it again even though you explain they can be fixed.
Anyway, I have been using a 3rd gen (Ivy Bridge) i5 as my "daily driver" for reading e-mail and such for a while. This was a leave behind and I upgraded the CPU from a lower end i3 or Pentium. I liked it for the 17 inch screen plus the fact I am more of an Intel fan overall.
I ended up being left with a 17 inch i7 today. It is a Sandy Bridge (2nd generation) and slower but is quad core. The unit also has a discrete graphics card.
I am curious as to which one you would use as a "daily driver" so to speak to read e-mail and the like. I do also watch videos and use this for the mapping/graphical work at times so that might play a role. Basic DVD, Blu Ray, and streaming video will play fine on either one.
Here are the two units. Both have 17 inch screens and HDMI ports.
Dell Inspiron 17R 5720 (newer one)
Chipset: HM77 (Ivy Bridge)
CPU: Intel i5-3380M 2.9GHZ dual core
Graphics: Intel HD 4000 (onboard)
USB ports: 4x USB 3.0
Ease of accessing hard drive/RAM: EASY! One screw and a panel removal are all it takes.
Cosmetic condition: few minor scratches (I don't care)
Power requirement: 65W
Dell Inspiron 17R N7110 (older one)
Chipset: HM67 (Sandy Bridge)
CPU: Intel i7-2670QM 2.2GHZ Quad core
Graphics: Geforce GT 525M (discrete) and Intel HD 3000 (onboard)
USB ports: 4x (2x are USB 3.0, 2x are USB 2.0) One of the USB 2.0 doubles as an eSATA port which never caught on so I don't really care.
Ease of accessing hard drive/RAM: Ram is easy, hard drive requires removal of keyboard and palmrest.
Cosmetic condition: Near perfect
Power requirement: 130W
The Passmark score on the older i7 comes in way higher than the newer and higher clocked i5. I will be using the same ram and SSD no matter which one I use so that doesn't matter. I figure the better discrete graphics card will more than offset the lesser onboard graphics. I personally vote for the older but higher end i7 unit.
Another possibility is to put the i7 into the newer unit as that motherboard would take it. I would lose out on the graphics though. I am not sure the i5 would work on the older chipset (some do, some do not) but I have a Sandy Bridge i5 on hand so that wouldn't be an issue.
What do you think? Leave the older unit as is and use that?
Conor

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