If it makes a drrrr sound, it has to be something mechanical that vibrates. This rules out your RAM atleast. It could be a device that has a fan, like your 3D card or your motherboard, or it could be your hard drive. If it is a fan that is faulty, the restart is likely to be due to overheating. I don't think a faulty hard drive would make your PC restart, but it could definitely make your PC get a bluescreen, and your windows installation could be set to automatically restart when you get one.
In that case, you can try turning off automatically restarting, and write down the error message you get. In order to do this, go to "System Properties" and then the "Advanced" tab. Here you press the "Settings" button under "Startup and Recovery". Now, uncheck the box for "Automatically restart".
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I missed the part where you said you didn't even get into windows. In that case, I think your best bet it to put your hard drive into another computer, and copy over the important data. After that, you could try checking whether or not it is the hard drive. If your hard drive works perfectly in a different computer, it is most likely not a hard drive problem. If it isn't your hard drive that is making the noise, the remaining options are the fans. There is likely to be 3 or 4 fans in your computer. One in the power supply, one on the motherboard itself, one on the CPU and there might be one at your video card, depending on its power. Try finding out which one is the source of the noise, and check if they all spin like they should. A nearby object could prevent a fan from rotating, and at the same time make a noise similiar to the one you described.
Be sure to discharge yourself of static electricity before poking your hands into your computer.
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