If I buy a 2133MHZ RAM for my Laptop which uses A4-6210 APU, would it perform at 2133MHZ or will it be downclocked to 1600MHZ ?
For that weak of a GPU, you're not going to notice a difference.
I would recommend checking with your laptop manufacturer to ensure that the memory you have chosen is compatible with your system.
As AMD Matt advised you need to check with your mobo maker to see exactly what RAM model, frequency and quantity that your laptop/mobo supports. The laptop owner's manual typically has this info. but it's worth confirming it with the laptop maker. You are unlikely to see any improvement from faster RAM anyway due to the entry level, low power, 15w processor design.
It turns out that the A4-6210 APU is a single channel design that uses DDR3L-1600. If your laptop maker designed the mobo to run the RAM at up to 1600 MHz. then that would be the faster RAM frequency you can obtain regardless of what DRAM you buy. Yes higher frequency DRAM can run at lower frequencies, but it's pointless to pay a premium for higher speed DRAM than you PC can use.
AMD A-Series A4-6210 Notebook Processor - NotebookCheck.net Tech
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