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#21
HD Audio has jack sensing, the AC97 does not.
Just checked and I couldn't find these cables anywhere on the motherboard... The only cables coming from the front of the case are the ones for the buttons and the hard disc access light. The front panel has just holes where the USB and 3.5mm jacks should be so I'm assuming they're not in the case anymore. I took a few pictures in case you'd like to take a look.
OK, then the cables and jacks are no longer there.
That leaves the Green speaker jack on the rear. The motherboard, from your pictures does no appear to have a slot for another sound card. If the Green speaker jack's volume is not loud enough, you have two options - a USB headset or a small "headset amplifier" like is used in recording systems.
Here is an inexpensive headphone amp. The Behringer allows 4 headsets but you can use just one. Can't beat the price.
https://www.amazon.com/Behringer-HA4...nger+micro+amp
You can also try one of these. It's cheap and works out of the box (I have one)...
https://www.amazon.com/Sabrent-Exter...xCL&ref=plSrch
Or choose from here...
Amazon.com: usb audio adapter
This is your front audio connector on the MB
You could get something like this to connect it to: Front Panel Audio: Computers/Tablets Networking | eBay
I have a USB headset and I notice no difference in quality. However, I am nowhere close to an audiophile, so take it for what it's worth.
If you do have another pcie slot, a sound card would work, but to use the front panel audio jacks you still need the wire from the FP connections to plug into the card.
In CountMike's picture the yellow circle shows where the FP audio connector should plug into the board. That wire may be in the bundle of wires coming from the FP connections. It is a logical assumption if the case has FP audio connections, it should also have the necessary wires to connect it. Look at the back of the FP connections and trace the wire from the audio jacks and find the other end of it.