Keep in mind that you should
only buy a Dell XPS 15 in a
configuration (link) that has the upgraded 1920x1080 B+RGLED display. The XPS 15 should not be bought in any configuration that has the stock 1366x768 display.
15.6" 1366x768 displays limit multitasking and productivity because they make things onscreen large, and they tend to have terrible image quality due to low contrast. I don't recommend this type of display to those who have a budget that allows them to get a laptop that has a better display and at the same time suits their needs, and who don't require large text for eyesight-related reasons.
On the other hand, the 1920x1080 B+RGLED display offered in the Dell XPS 15 is one of the best 15.6" displays available. In addition to its high resolution and high contrast, its high color gamut makes colors appear very saturated.
XPS 15 $100-off coupon code:
932N$0ZCCHWZB9
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More notes about your listed requirements:
- Don't make it a top priority to get a Core i7 processor unless you have a specific need. If you're looking for game performance, the GPU is more important than the CPU.
- The memory of a GPU past 1GB is generally irrelevant for game performance. The GPU core itself matters more. You shouldn't be looking for a GPU based on how much memory it has.
- You listed 6GB of RAM as a requirement, but again, what for? Most users don't need more than 4GB, but if you do need more then still don't make it a priority to find a laptop that has more than 4GB right off the bat, because you can upgrade the memory aftermarket for very little cost.
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What are the actual applications you're planning on using the laptop for? That will help us get a better feel for what components you need to pay particular attention to.