Auto giant General Motors is one of HP’s biggest clients. The company currently outsources about 90 percent of its IT needs, and its automobile business alone pays Hewlett-Packard $350 million annually.  The firms also announced a separate deal in 2010 that is valued at $2 billion, and there’s also a third one on top of that which is worth $600 million. Unfortunately for HP, this latter one might just go down the drain in light of the latest reports.

General Motors is driving away from its IT services deal with HP.

This week GM announced that it will be handling most of its IT in-house within a few years’ time, a transit that will involve the hiring of thousands of new workers. And insiders say that it might just pull the plug on the $600 billion services agreement with Hewlett-Packard because of that.

From Reuters:

“It is unclear how much of the HP agreement would be affected. But the GM contract is one of the bigger contracts at the IT company, one of the sources said, adding that the loss of a significant amount of that business would be a “big deal.”

The sources spoke on condition of anonymity because the details of the arrangement are private.

HP and GM both declined to comment.”

Hewlett-Packard’s services business accounts for $36 billion in revenue, which on the surface dwarfs any amount of money that the vendor could lose over GM’s latest internal change. But the car maker has been a key HP client for the past 25 years.

Previously HP extended its long time partnership with Turnkey to enterprise software testing. The two will offer updated versions of HP’s Application Lifecycle Management and HP Quality Center solutions.