As you will likely know by now, Microsoft's new operating system has now gone on pre-sale pre-order in the UK.

Under a promotional pre-order scheme, of which Microsoft says "stocks are limited and it is first come first served!", you can get the new OS for less now than you will have to pay in October.

The current RRP for the new software is £49.99 for Home Premium or £99.99 for Professional, rather than the full prices of £169.99 and £219.99 or even the upgrade prices of £79.99 and £189.99.

Various UK retailers are offering the new OS, but it seems to be Amazon - who has reported strong sales already today - is offering it for the lowest price.

Amazon is offering pre-sales pre-orders of Windows 7 Home Premium and Professional for £44.97 and £89.97 respectively.

DGSi Group companies, such as Currys and PC World are similarly low at £44.99 and £89.99.

There are links below to the stores, and more info on Microsoft's official site - although, somewhat embarrassingly for the company, it's currently down.