hi David, i know its a full 6 years on... but i finally upgraded my Quad socket H8QGi-f processors with a pair of 6380ES. They seem to be quite overclockable. i'm running them with the BIOS set to Downcore mode "Compute Unit" option. This CC6 power gates one core in each Piledriver Compute unit, essentially halving the # of cores presented to the OS. This really lowers the temps, and allows my 92mm Noctua NH-U9DO A3 coolers to cope with the temps. i think this way of doing this also gives an increased cooling area per core as the G34 chips have a larger heat sink contact area.

i'm currently running them at Pb0 - 4.473 GHz (single core turbo), and Pb1 - 3.727 GHz (all core turbo) with the ref clock at 213.



Quote Originally Posted by DavidMMM View Post
@rvborgh:
a) there is a kind of wall - for 6380ES - 4,1GHz and for 6386ES - 4,2GHz - from which, no matter the voltage you put in the CPU, they cannot cope with the benchmarks / stress tests. The 6380ES is limited by the +85-90mV given by the modified BIOS, but even if the 6386ES has not this problem, it cannot be raised more then 4,3-4,4GHz with all cores;
b) there is also an issue with the air cooling - assuming you are using Noctua 12cm coolers,with the air flow horizontal in a tower case - from HDD cage to the backplate/shield of the mobo,the dimensions of the cooler do not allow to install even 4 of the 8 DIMM's per CPU. Only Noctua 9cm cooler allows installation of all DIMMs as described above, but cannot cope with TDP 140W + overcloking. I'm using a Thermalright HR01+ and HR01 with custom made clip for G34, which allows me to install only 4+4 DIMMs.
c) as the Piledriver cores need a lot of power and the best single CPU arrangements are the 12+2 phases motherboards(Asus CH5-formulaZ, Asrock 990FX Extreme9), with 2 "Piledriver" cores glued together with a common L3 cache, the SM mobo 6 phase power supply is the issues - I don't think the cooling of the VRM will help more, and forcing the mobo will have dramatic effects regarding its remaining lifetime;
d) I will try a run with staggered cores if possible, as this arrangement will put a lower pressure on the mobo's VRM, unfortunately I have only two week-ends per month when I can play with my toys.