No audio from built in chip

Depending on your operating system, you may need to enable legacy audio support in the BIOS of the motherboard. This is usually done by rebooting and pressing one of the F keys. F1 or F2 usually, then you can check for the setting. There may even be an onboard audio enable/disable option.
Also try reinstalling the sound drivers for the motherboard as a windows update may have updated your drivers incorrectly.
Otherwise check if you have another sound card attached to your motherboard as well as this will usually take over from the built in sound. If so, either remove it or plug your speaker cables into the socket on the card instead.

Cheers