How to build gaming computer that can use minecraft without lag?

I'm wanting to build a customized computer since that's the only answer I get when I ask what computer to buy -.- Basically it doesn't have to be a supercomputer or anything, I just want to build one for a cheap price that can run minecraft with DECENT fps, because I'm sick of playing on 5-6 fps D:<

I have no idea what "parts" to buy though. I have very little knowledge of putting together computers, so if anyone could give me some tips, that'd be great!

Really for mine craft the computer doesn't need to be that powerful., If you start get high res textures and mods etc. You may need to. A really popular graphics card that could run even the highest textures well is the GTX 760. It really depends though. Make sure to look up tutorials on building computers to see what parts you need. You can also look at benchmarks to see which graphic card is enough to run the game. There's a channel on you tube called LinusTechTips have a look at that channel as they always look at graphics cards and compare them to other ones. Link will be in source.

Off of that now you will need a CPU and you need to find out what socket it uses so that you can get the correct motherboard for it. Then the other things are a Case to house the components in, RAM (easiest part to install), Hard Disk Drive (HDD), Power supply Unit (PSU), operating system and other parts are not essential such as optical drive, card reader but you may want them.

If you are at all intrested in buying a custom PC I'm trying to sell one and if you would prefer you can buy mine here is the link: http://www.gumtree.com/p/for-sale/custom-built-gaming-pc/1064344418

Hope I have helped you out.

If its only minecraft you want to play you don't need to build one as most decent computers can play it well and if you don't know anything about pc building its probably easier. Any £500+ computer will probably play it to a good standard and you don't need a fancy graphics card or anything. If you plan on playing more complex game though id recommend building one or using a service like pc specialist if you have absolutly no clue but you may be charged more than building it your self

Before upgrading, make sure the lag is not due to either your network connection or malware on the computer. In the first case, an upgrade won't help. In the second, all you need is to reinstall the OS (or get lucky with an antivirus product.)

If you do build your own system, get the fastest memory that your MB supports without overclocking. Spend a few bucks extra if you need to here. I stick to standard speed grades and don't O/C, but you can use your own judgement. Debugging hardware glitches isn't easy or fun, imho.