HP, the world’s largest PC maker, has said that it not be making any ARM based tablets. It will focus its energies on developing for the x86 version of Windows 8 when the platform debuts later in the year, a spokesperson told Bloomberg News.

The ARM version of Microsoft’s new tablet-centric operating system, Windows RT, was designed to go head to head with the dominant iPad series and Google devices – all of which use ARM based chips.

It is not a good sign for Microsoft if it can’t get one of its biggest partners to buy into its multi-processor platform strategy – especially since the company already has experience with ARM processors.

HP’s last tablet attempt, the HP Touchpad, was a resounding failure. It suffered price drops just months after its July 2011 release, before being pulled altogether. It utilised HP’s own WebOS operating system, a development and rebranding of PalmOS – which the company had purchased in 2010. The whole project was all but canned during HP’s leadership struggles.

HP’s spokesperson said that the decision was made after input from HP’s customers, and that the x86 Windows 8 "provides the best customer experience at this time and in the immediate future."

Microsoft has pursued a very selective strategy with the rollout of Windows RT, releasing early development code to a select few hardware makers, ostensibly to ensure a high quality experience. Microsoft also announced it would be releasing its own range of tablets, the Surface (ARM) and the Surface Pro (x86), which was controversial with its hardware partners.

HP’s first tablet will be focused on the business market, and the spokesperson told Bloomberg that the decision to drop ARM was made before Microsoft’s tablet and phone announcements a fortnight ago.

Another big PC maker, Dell, has also announced it will be producing tablets for Windows 8, but did not specify which version. It partially blamed iPads for its 33% fall in profits last quarter.

It highlights some of the problems Microsoft has been having attempting to migrate not just its services to the new mobile world, but in bringing its partners along. Using ARM chips means that legacy software, such as Windows 7 (and earlier) programs and apps have to be completely rewritten for the platform. Companies such as HP aren’t willing to take the gamble, especially since Apple’s ARM-based iPad hold a huge 63% market share in the mobile computing space.

ARM chips offer a superior price-battery performance ratio to the x86 chips made by AMD and Intel, which while significantly more powerful, have not been able to power mobile devices for extended periods of time.

Intel has not had much success in the mobile space for this reason – the company’s traditional focus on high powered desktop computers means that ARM has all but monopolised the mobile phone and tablet sector, with some 90% market share.

Orange Mobile did release the first Intel powered smartphone running its single core Atom Z2460 processor, but it has not seen any success.

Attempts by the legacy PC makers to revive their fortunes in the mobile space have led to the move to Ultrabooks, mimicking the success Apple has had with Macbooks, behind a huge campaign by Intel to drive adoption by other hardware vendors. The iPad already killed off netbooks, and Ultrabooks have had a tepid reposnse from the market due to their high price points (usually around £899-1299).