I already have a Gtx 970 and I have a low budget.

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An R3-1200 can still bottleneck a GTX970, however most games it would be minimal to nothing (for average frame rates). There will be more demanding games as it's not just about CPU draw calls sent to the GPU, and of course we'll still have 1% and 0.1% lows that are unavoidable with most CPU's.

*That doesn't necessarily change anything, but if you want better advice you should give us more information about the CURRENT SYSTEM you have because you can't just upgrade the CPU.

It would be preferable to have at least the R5-1400 (which is hyperthreaded). The R3-1200 islightly overclocked s similar to an i5-3570. So any 4-core CPU that's similar or newer should not be replaced with an R3-1200.

Even an AM3 CPU if heavily overclocked might...
An R3-1200 can still bottleneck a GTX970, however most games it would be minimal to nothing (for average frame rates). There will be more demanding games as it's not just about CPU draw calls sent to the GPU, and of course we'll still have 1% and 0.1% lows that are unavoidable with most CPU's.

*That doesn't necessarily change anything, but if you want better advice you should give us more information about the CURRENT SYSTEM you have because you can't just upgrade the CPU.

It would be preferable to have at least the R5-1400 (which is hyperthreaded). The R3-1200 islightly overclocked s similar to an i5-3570. So any 4-core CPU that's similar or newer should not be replaced with an R3-1200.

Even an AM3 CPU if heavily overclocked might not be worth upgrading with limited funds. In that case I'd recommend saving up for a bigger upgrade to get longer life out of the system (i.e. R5-1400 or R5-1600).

You may need:
1) CPU
2) Motherboard
3) DDR4 memory
- and look into Ryzen memory requirements (i.e. 3200MHz 2x4GB DDR4)
4) Windows license
5) reinstall Windows

Also, a "low budget" should be replace with an actual budget, and tell us exactly HOW you use the computer. If it's mainly for games what types of games? Mostly MMO's like Battlefield 4 or just offline single player?

PCPARTPICKER is quite handy to find and compare computer parts
 
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