Give a man a fish...
If you ask me what the current rate between JPY and USD is, I can tell you (about 95 JPY/USD). If you need to know the same thing again next week, or next month, and I'm not around, what will you do?
It may be efficient in the short-term to just tell you to use 95, but long-term if an important part of your work is knowing what the JPY to USD rate is, it's much better for me to teach you how to figure it out rather than just telling you the answer.
Now many people may assume this means I should just give you a link and then it will all be okay because you can find it next time. Problem solved, right?
What happens if you need to know the rate between USD and EUR? What will you do then? Of course I can give you another link, but then you will just have two separate links, and run in to the exact same problem if another currency is required.
This is no good.
Teach a man to fish...
What many good bosses will do is to ask you to think about it. When you think about it, you are developing problem-solving skills that can be used not just to finish the current task, but to be able to tackle future issues you aren't perfectly trained for.
So maybe it would be quicker to set up this computer if your boss told you the server name. But what happens for the next computer? Will he need to accompany you every time you set up a computer so that you can know the server name by asking him?
Think about it from your boss' perspective
Do you really think your boss doesn't want "to make sure something is done correctly than doing it wrong", or for "our department to be most productive"?
Of course he does. The difference is perspective. He can teach you the name of the server this time, and you learn nothing, and the lesson gets delayed (though the computer gets set up quicker). Teaching you earlier means you will be quicker in the future.
What he wants is for you to make an effort to forward their own education.
To go back to the currency example, if you need to use the JPY to USD rate in your work, and you look it up on google and a couple other sites, and can say, "I need to use the JPY to USD rate for work. I looked it up on Google and the rate was 95.74. Bloomberg says it's 95.61. What is our policy for which rate to use?" then it tells them you are trying to solve the problem, but need guidance on something only the boss can tell you -- what the internal policies are for which rate to use.
If your boss says, "We have an internal rate for official calculations, but for most work you can just use the google rate or the bloomberg rate, just make a note of the time/date/source of the rate you use in the document" then you never ever have to ask that question again (hopefully) as you can apply that knowledge to all your future work without asking. This makes their job easier, even if it takes you 20 minutes to figure out about foreign currency exchange rates on google and wikipedia beforehand.
So where does this leave you?
Perspective comes with age. You are 22 according to your profile, and while I'm sure you're well-intentioned, this is going to be a problem you encounter with almost any office. You said "I find it offensive the way he says it as if I'm dumb for not knowing it" but I think you are both misinterpreting his intention, and taking far more offense than should be required.
You are free to ignore my advice (and learn yourself a few years down the line), but for what it's worth, here it is:
Patience is a virtue
Welcome to the working world. There are many annoying people you will come across. Some will be spiteful. Some will be incompetent. Some will be obnoxious. To some of the people you work with, you will be the one they find spiteful, or incompetent, or obnoxious. Most people will be good decent people working hard to earn a living and enjoy their life.
Business is about people. As much as you may despise it, learning patience with people is a great skill that you will carry throughout your life. Or, like me, you can spend over a decade and still struggle with it from time to time. But at any rate, you should try. Patiently.
Do you like green eggs and ham?
You are young. While I wish you all the luck in becoming a giant in whatever you choose to do with your life, chances are you haven't figured out the best place for yourself yet (I doubt you really want to be inputting server names). This gives you a great opportunity to just try things out and see how they work. If they don't, you're young, you still have options.
The key to this though is to give it an honest shot. You may find your boss' inefficient, mistake-prone, and offensive, but he's the person you report to in exchange for your salary, so why not give what he wants a shot? If it doesn't work, you've learned that your gut was right on this one. And if it does work, you'll grow as a person and have learned a bit of patience and understanding for your fellow human beings.
Both are important. For normal folk like me, the latter is a lot more important because our gut is often wrong and we'd end up a sociopath if we always trusted it.
Pick your fights
At the end of the day, this is tiny. It's a boss not answering a question. Unless you let the stress get to you, it won't impact your life in any meaningful way. There are times to get pissed, like when you get turned down for a (well-deserved and promised) promotion or raise, or if you are told you have to move halfway around the world or lose your job. Getting pissed off about this issue to your boss will hurt you in the long run.