Some early upgraders to Windows Vista Service Pack 1 have been venting their spleens on Microsoft's Vista team blog complaining of compatibility issues.

The service pack was made publicly available just 24 hours ago.

"I downloaded it via Windows Update and got a blue screen on the third part of the update," wrote 'Iggy33'.

An equally unhappy 'SeppDietrich' wrote: "What a disaster. It exiled all my Nvidia drivers to the Bermuda Triangle."

'Bikkja', meanwhile, complained of performance issues, saying: "After installing SP1 things seem to go really slow, even though my computer shouldn't have any problems."

IT veterans will know that major software patches often come with attendant gremlins when first given a public outing. Early adopters typically rush to install the new software, encounter problems and then wait for Microsoft to fix them.

In a bid to manage user expectation, Microsoft has made it clear that Vista SP1 will not install on computers that use peripheral device drivers which the company deems incompatible.

The software giant has published a list detailing anticipated incompatibilities.

Microsoft claims that Vista SP1 features more than 300 fixes, including a patch that allows users to run the BitLocker encryption tool on multiple hard drives and an improvement in the speed with which the OS wakes up from hibernate mode.

Vista users can download Vista Service Pack 1 for free from the Windows Update site. Those preferring the retail touch can buy boxed versions from the likes of Amazon.