WINDOWS 95, the computer software launched last week on a £200 million wave of publicity, is slower than its predecessors, according to the first independent tests.

The results, carried out for PC Magazine, will come as a blow to Microsoft, the US company hoping to persuade millions of computer users to upgrade to its new product.

Industry commentators have already criticised the high-profile launch as masking a run-of-the-mill product. And the PC Magazine results show Windows 95 is in fact a step backwards in terms of productivity - which is the most important reason for upgrading software.

Technical experts compared it with its predecessor from Microsoft, Windows 3.11, in tests involving 13 different packages. Windows 95 proved substantially slower.

Specialist tasks showed some improvement using Windows 95, but the speed gains were typically less than 10 per cent.

Microsoft was not available for comment.