Compaq is to axe 500 staff from its three manufacturing operations in Scotland, and will shut down Tandem's development plant in Stirling.
Manufacturing will be consolidated in Erskine, combining the production processes from both the Tandem facility and the Irvine based Digital PC production operation.
Meanwhile Compaq's 300 strong services workforce based in Erskine will transfer to Digital's Irvine site.
The 500 job losses will mostly affect staff at the assembly lines. More jobs could also be lost among employees unable to transfer from existing facilities to the consolidated locations.
The redundancy process will be completed by the end of this year according to Compaq.
"We greatly regret the job losses but, unfortunately, in streamlining our combined organisation, whilst leveraging the strength of each, we have to reduce our workforce around the world and this obviously has an impact in Scotland," said George Devlin, vice president of European operations.
Compaq confirmed the 500 losses were the total for the Scottish manufacturing operations but did not rule out cuts in its call centre facilities also located in Scotland.
National newspapers reported incorrectly that 1,000 jobs would go.
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