Thank you for your answers. I was amazed that IBM is having the top place - my only experience with IBM was using an expensive server which decided to blow up the electrolytic capacitors from the motherboard after one year. Since my concern is reliability I will stay with IBM T series then which people say are for performance rather than X series that are for mobility. I don't need dual core since the support for this is scarce in many operating systems.
Thank you for your answers, I will read the thread for the new answers.
