The function of the Southbridge Chip

[poshgeordie]

This may be better in the Hardware section, but posting it here because increasingly there are more Southbridge (SB) issues being reported for T4x series.

This diagram shows the function of the Southbridge chip and consequently what problems can be experienced if one part becomes unsoldered.

On the diagram taken from an ECM motherboard, it shows the rock solid Intel 915 combined Northbridge and graphics chip, and the FW82801 Southbridge which is very similar to the one fitted to T4x series.

Note that the SB controls a lot of different areas on a PC / laptop, typically:

Hard Disk - HDD will stop working but will start again when pressing on SB
Audio - crackling or no audio
USB - runs in 1.1 mode rather than 2.0
Mouse
keyboard
Ethernet
Serial (and probably parallel) ports
PCI bus
etc

Note that a freezing display may be caused by one of the above and not the graphics chip.

[Norway Pad]

Thank you for once again providing us with good and useful information.

Back in the good(?) old days when I read about this stuff, the Northbridge dealt with the very fast components, being RAM, CPU, and later also the AGP slot. The Southbridge (or I/O controller, which I think it was also called) took care of I/O ports and the slower buses, like ATA/IDE and the PCI.

This is probably still the case today, but a lot more I/O that's built in to begin with..