For people in college/recent grads the thinking for large companies (think Boeing, Exxon, JP Morgan) is that college kids don't really know anything. The things they're taught in school is learning to learn. These large companies have kickass training programs so it doesn't really matter that you're an art history major and don't know anything about how to value a company for example. They want to see a high GPA (3.5 from a target school) in order to see that you have the base line capabilities of learning the skills required to do the job. The second part is motivation to do the work.
So with that background information in mind, the important thing, if i already have a high gpa, is how to show that you are motivated to do the work. This is where networking/connections come in. If you have someone vouching for you that you are interested well then great, clearly you want to work at the firm.
Personally, I did not know anyone at the company prior to applying. I reached out to alums and asked for informationals (can elaborate on this if curious).
Honestly you don't need connections if your resume clearly shows your motivation and capability. It's really hard for a student to show that just through resume, hence why networking is so important
I'm just going to take a second and talk about on a few things as a mechanical engineer undergrad set to graduate in May.
1) GPA minimums are highly dependent on where you went to school, your major, and whether or not that school believes in grade inflation. Also, GPA becomes less relevant with experience in the field.
2) Someone comparing JP Morgan, Boeing, and Exxon is business oriented, not engineering oriented, and therefore while the anecdotal post may be applicable to business majors, the people with the technological know-how may be in a slightly different scenario. Beware, though, that you must still convince the HR personnel to hire you.
3) The one thing Willy for sure has correct- Good engineering companies do a rotation of positions for entry-level engineers, such that engineers can get a feel for all different facets of the engineering environment. Typically the different areas (for mechanical) are designing, testing, manufacturing, and quality. I have seen companies that do between a two and a three year rotation between these positions.
4) Projects, besides being good for your resume, often provide the best experience to talk about in interviews. Don't be a jerk-off all college long. Get involved. Engineers, I STRONGLY suggest the SAE projects. I'm partial to the Formula/Formula Hybrid projects, but the Mini Baja, Supermileage, Aero, Clean Snowmobile Challenge, and CDS competition are all worthwhile. Do it. You'll likely learn more than you ever would in your classes, and it'll help you more in the grand scheme of things. If you want examples you can PM me, and I'll get around to it next time I show up here.