Kernel.org: 4.12
sid (unstable): 4.11.6-1
stretch (testing): 4.9.30-2+deb9u2
jessie (stable): 3.16.43-2+deb8u2
wheezy (oldstable): 3.2.89-2

Debian GNU/Linux device driver check & report

Toshiba: Satellite L550-203

PCI IDWorks?VendorDeviceDriverKernel
80862a40YesIntel CorporationMobile 4 Series Chipset Memory Controller Hubintel-agp
80862a42YesIntel CorporationMobile 4 Series Chipset Integrated Graphics Controlleri915v2.6.32-
80862a43Intel CorporationMobile 4 Series Chipset Integrated Graphics Controller
80862937Intel Corporation82801I (ICH9 Family) USB UHCI Controller #4
80862938Intel Corporation82801I (ICH9 Family) USB UHCI Controller #5
80862939Intel Corporation82801I (ICH9 Family) USB UHCI Controller #6
8086293cIntel Corporation82801I (ICH9 Family) USB2 EHCI Controller #2
8086293eYesIntel Corporation82801I (ICH9 Family) HD Audio Controllersnd-hda-intelv3.1.0-
80862940Intel Corporation82801I (ICH9 Family) PCI Express Port 1
80862944Intel Corporation82801I (ICH9 Family) PCI Express Port 3
80862946Intel Corporation82801I (ICH9 Family) PCI Express Port 4
8086294aIntel Corporation82801I (ICH9 Family) PCI Express Port 6
80862934Intel Corporation82801I (ICH9 Family) USB UHCI Controller #1
80862935Intel Corporation82801I (ICH9 Family) USB UHCI Controller #2
80862936Intel Corporation82801I (ICH9 Family) USB UHCI Controller #3
8086293aIntel Corporation82801I (ICH9 Family) USB2 EHCI Controller #1
80862448YesIntel Corporation82801 Mobile PCI Bridgei810_rng
80862919YesIntel CorporationICH9M LPC Interface ControlleriTCO_wdtv2.6.28-
80862929YesIntel Corporation82801IBM/IEM (ICH9M/ICH9M-E) 4 port SATA Controller [AHCI mode]ahciv2.6.25-
80862930YesIntel Corporation82801I (ICH9 Family) SMBus Controlleri2c-i801v2.6.25-
10ec8136YesRealtek Semiconductor Co., Ltd.RTL8101E/RTL8102E PCI Express Fast Ethernet controllerr8169v2.6.25-
10ec8172YesRealtek Semiconductor Co., Ltd.RTL8191SEvB Wireless LAN Controllerrtl8192sev3.0.0-

Realtek RTL8101E/RTL8102E Ethernet Controller and Realtek RTL8191SEvB WLAN Controller are used in several different Toshiba Satellite laptops.
I've seen a report on the L505-13J of 16 February 2011 that states neither work out of the box.
However on my machine, running Sabayon GNU/Linux, both do.
Admittedly, it's over a year later now (30 March 2012). (2012-03-30T12:47:55+00:00)