SD Card slot
PCI-based SD Card slot
This implementation is called "SD Card with IO support", and supports in addition to regular SD memory cards also special SDIO cards (e.g. Bluetooth, WiFi, etc).
lspci reports it as a Ricoh device with PCI ID 1180:0822 (X Series, Z60m, Z60t), or 1180:0841 (Z Series).
The sdhci project has developed a driver that supports these and other SD controller chips. The driver has been reported to work on ThinkPad X40, X41, Z60m, Z60t, X60 and X61 models, and has been available in mainline kernel since 2.6.17-rc1. See also "How to get the internal SD-CARD working".
Models featuring this Technology
USB based SD Card slot
This implementation only supports SD Memory cards.
Should be supported by the Linux USB Storage drivers (usb-storage).