There are a few ways to check your motherboard information.
The first place is to check any materials that came with your current motherboard. If you have built your own computer, you may still have the motherboard's user manual laying around. This will give you the general specs of the motherboard, like the ones mentioned above. If you didn't build your computer or if you purchased it from a retailer, you still may be able to check on the information regarding the manufacturer of your computer on their website.
Another way is to look within System Information on your computer itself. Most operating systems will have an option to view statistics regarding your machine, like what type of OS is running, what type of video card, processor, etc. If you're just looking for the basics - like processor type - this is a good place to go. Again, depending on your OS, System Information may be found within the Administrative Tools folder.

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A third way to check is by using third party software. These types of software scan your computer before sending you the results in a user friendly interface. A good program to use is CPU-Z. CPU-Z gives you important information like the name of the manufacturer, the BIOS brand and version, the model number, the chipset, and many other important information. CPU-Z and other products are usually free to download and free to install.
Looking for the motherboard information is quite easy and doesn't take much time. Having this information at hand will make it easier for the next update or upgrade that you do.
Image content - CPU-Z interface @ CPUID.com