Ummm, you don't.Just the name they use to identify the audio portion of the computer.(Dell / Microsoft)To explain;Chip and Chipset are slang terms for I.C.Integrated Circuit,
http://en.wikipedia.org/wiki/Integrated_CircuitThe Chip, or Chipset (You can use either word), for sound; is the audio chipset.If the audio chipset is mounted (Soldered) to a Printed Circuit Board, or also known as Card; it is a Soundcard.Removable, therefore replaceable.If the audio chipset is soldered directly to the motherboard; it is Integrated Audio, and not replaceable. (At least not easily)The Dell Optiplex 360 Desktop PC uses Integrated Audio.If indeed you do have a Soundcard installed, it would be mounted in a PCI slot on the motherboard, and it's outside bracket would be in an expansion slot, in the metal framework of the computer case.
http://www.redplanettrading.com/ebay/cases/optiplex360/empty/smt/opti360-back-800.jpgThere are four such slots shown, in the empty Dell Optiplex 360 Small Mini, computer case shown above. They are at the bottom.This is an example of a Soundcard,
http://en.wikipedia.org/wiki/Audio_adapterPerhaps you had no audio, went into Device Manager, and saw NO Device, listed.This means Windoze lost the Drivers for the audio chipset.Driver: Small piece of software that allows the Operating System to communicate with a deviceDo not know what the O/S is.The audio chipset is the device.Post what version of Windows you are using.In the meantime I'll use Windows Vista 32-bit as an example, as this is what the computer was supposed to come out with;Dell Support > Optiplex 360 > Drivers & Downloads page,
http://www.dell.com/support/drivers/us/en/19/Product/optiplex-360The page automatically comes up with Windows Vista 32-bit, drivers; listed.If you use a different O/S, click on the blue Down Arrow, to the right side of the box that has Microsoft Windows Vista 32-bit, in it.(Under the blue Operating System subheading)Here we see only 1 Audio file listed.Click on the blue down arrow to the left of - Audio (1)Click right on the blue name - Analog Devices - DriverNow click on the blue - Download File - to the left of -Update package for Microsoft WindowsMake sure there is a Green dot in the small circle, to the left of -Download and save the file.Then click on Continue in the blue oval.[If there isn't a green dot, click in the empty circle ](Suggest install it yourself. Automatic features have a tendency to scr-ew up)Green dot needs to be in small circle to the left of -Single-file download.Click on Continue.A small window will come up on the right -Opening DRVR_WIN_R216290.EXEClick on Save FileAnother small window will come up on the left.Allow the file to download all the way, then DOUBLE-click right on the file name.(If somehow a Microsoft 'squawk box' comes up, ignore it."Warning this software does not have a digital certificate, ya-da, ya-da. Just click on OK. It is Okay.At the bottom of the next 3 small windows, click on Next, Next, and Finish.Close all windows,restart your computer if not asked to do so.For additional questions please post in a Comment.Regards,joecoolvette