Overclocking stability tips for 1156
Overclocking stability tips for 1156
Hello everyone!
I'm looking for some experienced Lynnfield-1156 veterans to assist an older 486 OC board. I've studied several guides and understand how overclocking these boards works properly. I've found my Bclk to be steady, the RAM seems stable, but increasing the CPU multi-apps has caused crashes now.
In short, I'm using a p7p55m M/B, i5 760, with 2x4gb CL7 and 1600MHz RAM. My Bclk stayed at 1.22v @ 200, estimating a Vcore range of +0.22 to 24 (giving about 1.38-1.4v). I gave up on 4GHz (20x200) and settled for 3.8 (19x200). Adding a 1000mV CPU voltage increase seemed like the last adjustment for stability – mostly BSODs were replaced by app crashes.
I've also upgraded my cooling setup, adding a second fan to my CM212+ EVO, which raised my temps to around 72°F (previously over 80). The case stays open and fans run loudly, but power usage isn't a problem. Noise levels are normal.
Recently, I tried pushing the system hard by running a P95 blend test with 7000MB RAM, setting priority to idle, then stressing it out. I didn’t exceed 74°F and didn’t notice any issues with the PCIe or heat.
I’ve removed IMC Vcore voltage from my setup, as it was affecting stability (though it still crashes apps). The 19 passes on Memtest86+ were solid when timings were manually set – 7-8-8-24-1t-1600 at 1.5v.
IMC Vcore adjustments didn’t help; raising it to 1.55 didn’t prevent crashes. Lowering RAM multipliers improved stability, but not enough. Raising DRAM voltage to 1.55 still caused crashes.
CPU QPI and Ram multipliers were kept at their lowest settings (6.4GHz) to avoid crashes. Changing QPI back up didn’t help either.
PCIe voltage was increased, but apps still crashed. A second CPU was tried – it was stable most of the time, then crashed apps again, suggesting a RAM or memory issue.
During P95 or IBT/OCCT tests, the multiplier would drop to x9, 1800MHz for a few seconds, then jump back up. It might be throttling, but not getting overheated. Even with it on, I still see dips, usually settling around 1.386.
I’ve disabled PCIE auto-on and kept it off, which reduced dips slightly. But I’m unsure if over-voltage is the cause.
Other notes:
- I used a 2nd CPU (i7 860) – same symptoms, mostly stable then crashes.
- During tests, multipliers dropped to x9 for 10 seconds or so, then returned.
- PCIE voltage bump didn’t help.
- RAM voltage at 1.5v for 1600 was too low; I kept it at the lowest setting.
- I disabled CPU TM and other power-saving features.
- BIOS settings were mixed – some enabled, others disabled.
- I disabled CPU TM function and other advanced features without much impact.
Basics:
- Bclk: 200 (for 19-core CPU)
- Xtreme Phase Power: En
- All power-saving states and C1E/C-States disabled
- RAM timings set manually; no change made
- Turbo mode off
- PCIE voltage at 100
- Vcore around +0.024 (about 1.396–1.4)
- IMC Vcore bumped to 1.25, no difference
- RAM set to auto, still crashes
- RAM voltage at 1.5v, increased to 1.55 didn’t help
I haven’t changed QPI back, just left it at the lowest setting.
Trying manual RAM timings or changing cores hasn’t helped. I’ve tried using a larger PSU, adjusted clock skew, and more RAM, but nothing has resolved the instability.
Testing with 2 sticks in different slots helped, but still crashes. I’m running out of time – any tips on improving stability would be appreciated!
Check if your Bclk remains stable at 200 and isn't limited to a short P95 blend.