The University of Denver 2015 - 2016 recommended PC Laptop Manufacturers are Apple and Dell.
A Dell webpage meeting the minimum and recommended specifications for University of Denver students can be found at: dell.com/DellU/Denver
It is important to note that technology changes daily and prices fluctuate based on supply, demand and newer technologies. It is important to shop around and compare products, components and prices.
Here is an interesting article by Fortune listing the top laptop vendors among students in higher education.
SquareTrade Laptop Reliability Study
Warranty provider SquareTrade completed a laptop reliability study in 2009, randomly selecting over 30,00 laptops and netbooks to study 3 year malfunction rates by hardware manufacturers.
Of note is that 1/3 of all laptops will fail in 3 years and that netbooks are 20% more unreliable than laptops.
This study is purely on hardware failure rates and not on customer service or support by manufacturers. When selecting your laptop, always keep in mind the type of warranty that is purchased. Next day on site support like Dell is preferable to mail in depot like Lenovo.
PDF study by SquareTrade:
NOTE: If purchasing through retail companies such as Best Buy, please also upgrade systems to 3-4 years of warranty support.