Hello, I changed my motherboard from an ASRock Fatal1ty 990fx to a Gigabyte ga-990fxa-ud3, and now my pc is a lot slower. My CPU is the AMD FX 8120. I also changed from the stock cpu cooler to an after market one. PLEASE help!
As rolli59 said there is no reason your system would be any faster or slower going from one 990FX chipset motherboard to another. There only reason I can think of to even do that is if your old board died or to maybe add expansion slots.
Is Intel faster? Yes. But the only way to tell is in benchmarks or a side by side comparison and the difference is a few frames per second in some games or finishing tasks like encoding video a bit faster. In everyday use you would never be able to tell.
List all of your components. Are you sure you have all the latest motherboard drivers from the Gigabyte website? Don't use the CD that came with the board.