I'm (happily) running a 2001-vintage Dell Optiplex on Slack 12.0. At boot several i2c modules are loaded: i2c_i810, i2c_core, i2c_algo_bit.

'lspci' reports a few items that *might* involve 12c, namely the VGA controller and the SMBus:
00:00.0 Host bridge: Intel Corporation 82810E DC-133 (GMCH) Graphics Memory Con
00:01.0 VGA compatible controller: Intel Corporation 82810E DC-133 (CGC) Chipse
00:1e.0 PCI bridge: Intel Corporation 82801AA PCI Bridge (rev 02)
00:1f.0 ISA bridge: Intel Corporation 82801AA ISA Bridge (LPC) (rev 02)
00:1f.1 IDE interface: Intel Corporation 82801AA IDE Controller (rev 02)
00:1f.2 USB Controller: Intel Corporation 82801AA USB Controller (rev 02)
00:1f.3 SMBus: Intel Corporation 82801AA SMBus Controller (rev 02)
01:07.0 VGA compatible controller: nVidia Corporation NV5M64 [RIVA TNT2 Model 6
01:08.0 Multimedia audio controller: Ensoniq ES1371 [AudioPCI-97] (rev 09)
01:0b.0 SCSI storage controller: Advanced System Products, Inc ABP940-U / ABP96
01:0c.0 Ethernet controller: 3Com Corporation 3c905C-TX/TX-M [Tornado] (rev 78)

I don't use the VGA controller, but an old nVidia card.

So, my question is: why can't I drop those i2c modules and save some memory? What are they doing for me?

Yeah, I've RTFM'd myself to death, but the docs are impenetrable to me at least.

Help, anyone?

HaroldWho

CAUTION!
I am now way an expert on i2c and only just understand what it is used for. Although i may be wrong in my understanding on how it is used

i2c is a simple bus system. It can be used to connect devices together that only need a slow bus to talk to each other.

One use on computers is to provide a system for connecting things like temperature, voltage and fan speed devices.

Some things to read,
http://en.wikipedia.org/wiki/I2c
http://www.linuxjournal.com/article/1342

And a quick google search produces this
http://www.google.co.uk/linux?hl=en&...G=Search&meta=

Just drop them. You can easily monitor your voltages, etc.- as suggested - with adding your chipset under the Hardware Monitoring section of the kernel config and using lm_sensors.

You can drop if you want. If your hardware does not support, no need to use them. Edit /etc/rc.d/rc.modules and comment those.