I think the closest thing you will get to it is here: [Register or Login to view links] Sponsored Links
Here's the hardware differences which u asked for:
20 gig model number: CECHBxx: 4 usb ports, linux capable, hardware based ps2 emulation, SACD playback.
60 gig model number: CECHAxx: 4 usb ports, wifi, linux capable, hardware based ps2 emulation, SACD playback, Flash memory readers.
60 Gig model number: CECHCxx 4 usb ports, wifi, linux capable, Partially software-based ps2 emulation, flash reader, SACD playback.
80 Gig model number: CECHExx 4 usb ports, wifi, linux capable, Partially software-based PS2 emulation, SACD playback, Flash memory, Some models came bundled with Metal Gear Solid 4 or MotorStorm.
40 GB model number: CECHGxx, CECHHxx, CECHJxx 2 usb ports, wifi, linux.
80 GB model number: CECHKxx, CECHLxx, 2 usb ports, wifi, linux capable, Later models came bundled with Greatest Hits versions of Metal Gear Solid 4 and Killzone 2 (only at select retailers).
160 GB model number: CECHPxx, 2 usb ports, wifi, linux capable.
120 GB slim: 2 usb ports, wifi, cant install linux on this model, bravia sync xmb control, smaller form factor.
There you have it enjoy instead of looking somewhere else cheers!