Out of the 1000 units of 9900KS recieved by Overclockers UK from Intel, 500 units were taken by 8 Pack for special projects and speed binning. Over the past couple of months 8 Pack has being speed binning these processors to offer these guaranteed speed binned processors for those who want guaranteed overclocked all core performance.In our testing we found only a small percentage of CPU\'s can achieve 5.2GHz all core, as such we offer these guaranteed premium 5.2GHz all-core CPU\'s for a fair premium. Features:- Pre-Binned by 8 Pack and guaranteed all core 5.2GHz- 1.35v1.4v required to run stable- 240 AIO cooler or larger required- Tested in Asus Maximus 11 Hero Mainboard- Tested with 32GB 8 Pack 3600MHz memory (Samsung B-Die)