Agree the bigger the consulting company is, the worse it likely is.
IBM and HP are mostly consulting services and if you are with the wrong company in a consultant role (mostly the big corporations) you are more likely to get overworked for average to mediocre pay. As long as they can bill you though, they will typically keep you employed.
IT roles in Silicon Valley and startups may be considered cut throat as well, but I'm not sure those are much different then anyone trying to start a "new" business in any sector.
If you work in an IT department for a company (still private sector), it typically isn't as bad.
Some IT roles may still require you to work overtime or off time hours (evening / weekends) depending on whats going on or for support, but I wouldn't call that cut throat.