VR-Zone has posted news about a Hyper-Threading adapter for non-HT P4 boards
Things have gone quite well since we discovered there is a possibility of enabling HT on current P4s. PowerLeap has designed an adapter to allow hyperthreading (HT) on non-HT-ready P4 motherboards. It makes the pre-HT versions of the i845 and i850 allow HT to be enabled. However, it still doesn't enable HT on non-HT P4s. Intel is launching the new Pentium 4 with HT enabled from speed grades of 2.4Ghz onwards in a couple of months time so users might wish to upgrade their processors and enjoy HT without changing their older i845 and i850 boards using this adapter.Read more
