Notes: I believe that you need administrative permissions to do all of this, else you will not be able to do it all. Also, this is for Windows, you may need to find a different way to do this on Mac and Linux.This guide will go over many ways to speed up minecraft and boost FPS, there will be separate tutorials for different things, you can do these in any order, but you have to follow the steps in order.
I am not one of those people that will tell you to set your settings to minimum and try to make some quick points on PMC, but if you have a slow computer and your settings are of "Fancy" and "Far" then well, you should put fancy to fast, and far to normal or lower, I do not recommend minimizing the distance to tiny, unless you have a computer from the stone age, because you can use other tips to speed it up.
If you have an older version of a program then it will (most likely) not be faster than the newer versions, because the makers try to make things faster and faster. So if you have an older version of Java or another program that minecraft uses to run, then you may want to update it, I used to use an older version of Java, then I updated and I would guess that my minecraft speed was up by about 1.2x, so if you do have an older version, UPDATE!
As you probably know, windows makes a program called "Game Booster" which turns off all un-useful things on your computer, eg. printers, toolbars, and other background programs. Look for it at http://game-booster.soft32.com/free-download?gclid=CO6jkIahiLACFWLktgodTG_DOg
, which is where you can download it. This is completely free, so I don't see why you wouldn't use this even if your computer already is fast!
As you probably know, there are mods to speed up the game, which I will not go into detail about here, just do a quick google of something like "Optifine", or the other one, of whom's name I cannot think of at the moment.
I know that you didn't want me to come to this, all you modders with slow computers, but sometimes, to get the whole quality of minecraft, you have to stop the mods. The reason for this is if the minecraft has to read more data in your mods folder or your bin folder, then it has to read more at once, causing it to slow down, although, if you care more about mods then about 600$ then you can...
If all else fails, maybe it is time to upgrade your computer, I will not discuss this process here, in this case, use google to help you, and the MCForums!
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