Game and Gamestation no longer sell pre-owned Xbox 360 Core, Arcade or 20GB non-HDMI models, Eurogamer can reveal.
But trade-ins will still be accepted.
A spokesperson for Game told Eurogamer that people don't want the older machines any more. This, he said, represented a focus on the newer machinery.
But sources within Gamestation told Eurogamer the "high failure rate" of the old consoles was to blame.
An internal Gamestation bulletin read:
"As of Saturday 3rd September we will not be selling Pre-owned Xbox 360 Cores, Arcades and 20GB non HDMIs. This is due to the high failure rate of the console and the difficulty and cost of repairing them.
"We will continue to trade these consoles in but they will need to be sent back to the DC as a regular faulty return where they will exit the business."
The Xbox 360 Core was the original entry level Xbox 360. It contained a wired controller and cables that only allowed SDTV resolutions. The Core model was replaced by the Arcade model in October 2007. The Arcade had HDMI output.
The 20GB non-HDMI Xbox 360s were the first batch of Premium machines. These later gained 60GB hard-drives, HDMI output and an improved CPU heatsink.
Microsoft decided, in early 2007, to extend the warranty program for Xbox 360 for three years following the infamous Red Ring of Death saga. Microsoft said there were an "unacceptable" level of repairs that had to be made, and put aside more than $1 billion to deal with the issue.