Graphic Design is usually towards web-based content, printing, illustrations, etc. You can land a graphic design job is you have talent (a diverse portfolio) and experience. A degree in graphic design is usually 4-years, so its not something you can pick up in a semester or two. Its hard to find a job in graphic design unless you have either the talent or a degree. My good friend does freelance graphic design for webpages, and he's making around 40K a year, but he's just finishing up school. He plans on making 100K very soon (keep in mind he's very very good.) The people who make 100K are usally art directors, and they are in the position not because they are good with Photoshop, but because they're good artists. They understand what works and what doesn't, so their job is to direct their groups work in a certain direction on a project by project basis. .
If you're looking at Eidos or Valve ... considering you want to do graphic design, then your main position would involve storyboarding, character design, or even character texturing, mostly stuff of 2D nature. The gaming industry is a very difficult industry to stick to, so the people who are around longer make more money .
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