Microsoft will release two important Serial Packs (SPs) for Windows XP and Windows Vista. So far, the older OS gets a much bigger increase in speed when compared to the newer Vista.

Despite the fact that Microsoft has rather recently pushed on the market its latest operating system named Windows Vista, it now decided to give a hope to those still using the older Windows XP. Perhaps this decision was made by Microsoft because the sale figures were not so high for Windows Vista especially for business users who still hold on to their old XP system.

Both Windows Vista and Windows XP will get an update next year, but it’s the one for XP which catches attention, as testers who had access to the patch claim it brings a significant increase in speed. “We were pleasantly surprised to discover that Windows XP SP3 delivers a measurable performance boost to this aging desktop OS,” said Craig Barth, Devil Mountain’s chief technology officer, in a post to a company blog Friday.

Although the benchmark tests focused on Microsoft Office, informal reports on blogs and social news sites have reported that SP3 gives XP a speed boost. So far Microsoft has only publicly said that SP3 will address bugs and fix security flaws, so the performance gains, if true, would be an unexpected bonus for XP users.

On the other hand, the same tests on Vista SP1, have shown that the speed boost the upgrade promises is quite insignificant.