Discounted Xbox 360 models outsold the new slim SKU in June, according to NPD data.
Revealed by Michael Pachter in a note to investors, the new Xbox 360 S accounted for 40 per cent of sales during the month, while 35 per cent of sales were of the Arcade unit, which had seen its price drop to $149 in the US.
A promotion by Wal-Mart also bundled the console with a $50 gift card, effectively giving the Arcade unit a $99 price point, noted Pachter. Elite and Premium models made up the rest of sales.
Microsoft boasted last week that sales had jumped 88 per cent year-on-year following the new SKU and price drop.
"It is clear that the sales spike for the 360 was largely temporary, as clearance items accounted for around 60 per cent of total sales, and it is not clear that software attached heavily to these purchase," said Pachter.
The new model was launched in the UK on Friday, with Chart-Track noting that the 250GB model surpassed sales of the remodelled PlayStation 2 slim and the PlayStation 3 slim in its first two days.
It also said that sales of the console were around the same as the original Xbox 360 launch in 2005.