It could be graphics or sound. The vids not very clear, but there should be some numbers and or letters near the slot. Type them into google with your make and model and that may shed some light.
the sound card is intergrated... i think you could have somthing on graphics card as it is near the graphics processor... tried googling... and no results!
i thought of that... but the PC2700 it takes dont fit it.... and i cant find ANY ram on the net that has no gap in the middle of the connectors... unless it's designed to be homebrew or summat...