Hi Voltazar, just a follow up, are you using 1:1 ratio for FSB and DRAM? As that will give you a more stable overclock.
I've just realized we also have the same RAMs!!! This model is a bit weird... as it would not be stable even if I set 1066 with 2.1V... Damn OCZ for discontinued of their Blade series...
My ram is stock 2.1v 5-4-4-15 DDR2 800MHz though, bought it off newegg for $45 last year.
I installed the turboV program, and tried playing with the voltages by going in small increments with the NB voltage and FSB termination voltage to find a stable voltage for 4.0GHz, but with little success. I have faith that this CPU can reach 4.0GHz 100% stable.