Overclocking 8350 - Illegal Summout

[GustavoGimpel]

So, I've been trying to push my 8350 to 4.8Ghz ( I'll create an OC Profile for heavier games and video rendering, but I'll run it at stock for a day to day basis). The thing is, I've hit a wall and cannot go further. I'm using only multiplier to overclock it.

I'm currently at 24x Multiplier and 1.49v, and was getting some rounding errors on prime95 on Blend test. I did some research and found out I had to do some overclocking on my NB and HT Link, so I bumped up their voltages a bit and settled them both at 2400Mhz, which made the rounding error stop, and I could run prime95 on blend for about 30 minutes (sometimes, less) until I start getting Illegal Summout errors on some Workers.

The weird part is that it doesn't seem to be insufficient vCore, since it doesn't matter if I put 1.48v, 1.49v, 1.5v, the vCore (Using Ultra-High LLC) doesn't go past trough 1.512v on HWMonitor, and yet I'm not managing to get it stable. During prime95, my maximum temp is 68ºC (I know it shouldn't pass 72ºC) with my H100i on maximum (surfing between 1.48v and 1.5v shows no increase in heat because the CPU keeps switching between 1.5v and 1.512v when on stress test).

Cool'n'Quiet: Always Disabled
C1E: Disabled
SVM: Disabled
Core C6 State: Disabled
HPC Mode: Disabled
Apm Master Mode: Disabled
CPU LLC: Ultra High (Setting this to EXTREME when near 1.5v freezes the pc when on Prime95)
CPU Current Capability: 130%
CPU Power Phase Control: Extreme
CPU/NB Current Capability: 130%
DRAM Current Capability: 130%
AMD Turbo CORE technology: Disabled
CPU Spread Spectrum: Disabled
EPU Power Saving Mode: Disabled

RAM: G.Skill Ares 2x4Gb 2133Mhz CL9 (Using XMP Profile, didn't mess with overclocking RAM)
CPU Manual Voltage: 1.49v
CPU/NB Manual Voltage: 1.30v
DRAM Voltage: 1.65v ( It's advertised to run like this, I didn't touch it)
NB Voltage: 1.20v
NB/HT Voltage: 1.22v
NB Frequency: 2400Mhz
HT Link Frequency: 2400Mhz

CPU Temps With the Overclock:
Stays at 25-30 ºC when Idle.
Peaks at 58-68 ºC under load.

The Motherboard is a Crosshair V Formula-Z. The PSU is a NZXT Hale90 1000w Gold. I've checked all rails and they are completely fine, too little fluctuation. My H100i is Stock and fans are set to maximum RPM. Case fans are also set for maximum RPM.

Any idea on what might me causing the instability?

 

[Dark Lord of Tech]

Sounds like you have hit the limit of the CPU's potential.

 

[huvik]

^^ +1 to what he said, that is the luck of the chip lottery.

 

[huvik]

Also I think your over the max recommended temperatures for your CPU

 

[GustavoGimpel]

Could it be? I've managed to get it stable (24hrs Prime95 on Blend) at 4.7Ghz, and by increasing the vCore only about 0.02v, it managed to run at 4.8Ghz for 30 minutes before Worker #7 gave up. There isn't anything else I can do to achieve a bit more stability? Maybe push the NB and HT Link a bit further... I don't know. Maybe the VRM's are overheating causing the instability..

 

[Dark Lord of Tech]

I wouldn't push it anymore.