As there is a thread for PS2s, I thought we should have one for PS3s. There are quite a few test PS3s around, originally they were the original 60GB models (DECHA00x) with all the chips which meant after a few firmware upgrades they could play PS2 with hardware emulation which meant they were the only machines that could play PAL PS2 games in hardware... Later models (DECHJ00x) were based on the later models so you lacked the memory card slots, the 2 usb ports and the hardware emulation. By default they came with 40gb hard drives. Prototype machines tended to be one of the above but were not certified, apart from that they have no differences to standard machines, the original prototype machines do not have the test logo on them and had several stickers at the bottom. There are slimline test units too (DECH2x00x), these tend to be harder to find in the wild but they do exist, they lack the same functions as the slim line machines do. Show / exhibition machines tend to lack the test marking on top of the machines and will have an S prefix in them. Demostration units are another type of test/debug unit, the main difference is that they have a special firmware which is mean to lock out most functions of the unit, so only the game on the unit can be played and a few other function like photo viewing is possible. Not all demostration units are debug machines (as later ones were standard units with the special firmware) and the only way to tell is by looking at the model number sticker.