Sounds good, let us know how it goes!

What Asus motherboard do you have?Like Mike asked, what is your ram rated at. If you have 1333MHz ram and are trying to run it at 1523MHz that maybe part of your problem.In regards to your OC, rather than have CPU Ratio on auto you should plug in a number, 20 would be for your current 3.8GHz at a BCLK of 190. Below are the OC settings that I had for my i7 950 P6T Deluxe v2 system. Note that the ram settings under DRAM Timing Control are for the ram that I had, you will need to adjust them for the ram that you have. When overclocking there are some settings that it is recommend to disable, this provides for a more stable overclock. Note that Intel SpeedStep Tech, Intel Turbo Mode Tech, CPU Spread Spectrum, PCIE Spread Spectrum, C1E Support, Intel Virtualization Tech, CPU TM Function, Execute Disalbe Bit, Intel HT Technology, Intel SpeedStep Tech, Intel Turbo Mode Tech and Intel C-State Tech are all disabled.I suggest that you read these i7 9XX overclock guides, they explain what to do and how to do it.http://www.clunk.org.uk/forums/overclocking/22106-core-i7-overclocking-guide-beginners.htmlhttp://vip.asus.com/forum/view.aspx?board_id=1&model=P6T+Deluxe&id=20081220191040237&page=1&SLanguage=en-usAI Overclock Tuner: ManualCPU Ratio Setting: 21xIntel SpeedStep Tech: DisabledIntel Turbo Mode Tech: DisabledBLCK Frequency: 200PCIE Frequency: 100DRAM Frequency: DDR3-1603MHzUCLK Frequency: 3208MHzQPI Link Data Rate: Auto (3600 MHz)DRAM Timing Control1st Information :CAS# Latency: 6DRAM RAS# to CAS# Delay: 7DRAM RAS# PRE Time: 6DRAM RAS# ACT Time: 182nd Information :DRAM Timing Mode: 1N CPU Voltage: 1.32500CPU PLL Voltage: 1.82QPI/DRAM Core Voltage: 1.34375IOH Voltage: 1.20ICH Voltage: 1.20DRAM Bus Voltage: 1.66Load Line Calibration: EnabledCPU Spread Spectrum: DisabledPCIE Spread Spectrum: DisabledAll Other Settings: AutoAdvance CPU SettingsCPU Ratio Setting: 21x C1E Suppport: DisabledHardware Prefetcher: EnabledAdjacent Cache Line Prefetch: EnabledIntel® Virtualization Tech: DisabledCPU TM Function: Disabled Execute Disable Bit: DisabledIntel HT Techology: DisabledActive Processor Cores: AllA20M: DisabledIntel SpeedStep Tech: DisabledIntel Turbo Mode Tech: DisabledIntel C-STATE Tech: DisabledUnder Advanced Menu: PCIPnPPNP OS = Yes

Motherboard is Asus P6T (not Deluxe, just P6T)RAM is rated at 7-7-7-24 @1600Mhz.

Motherboard is Asus P6T (not Deluxe, just P6T)RAM is rated at 7-7-7-24 @1600Mhz.

Then the ram settings that are shown in your BIOS pictures are correct!

According to the screenshot tutorial you've provided, they're acheiving 4.0Ghz on a very similar system with much lower Vcore voltage of 1.250v versus mine that is set at 1.325v. I will read all this and most likely start from lower base clock like Mike suggested and go up. It's kind of hard to predict now when I'm not around the machine. I will report back either late tonight or some time tomorrow morning. :)

You need to keep in mind that all systems are unique when it comes to the amount of voltage it takes to keep a system stable at any given CPU/BCLK setting. Your 1.325V is not bad just because someone else has 1.250V, maybe they just got a hold of a golden CPU!The higher your clock the more voltage it takes and these voltage curves are exponential, not linear.

Ok guys, here we go:Mobo DefaultsBIOS flash: OKCPU Ratio: x12DRAM Timings: 10-10-10-24 (it would not allow me to acheive 11-11-11-24, it'd allow me 11-10-10-24 so I went with all equal values, shouldn't matter right?)BCLCK Freq: 200 x12Vcore: 1.3vSystem: Stable at two Prime95 runs at 7 and 5 minutes each.Temps: Around 69 degrees max, with cores 2 and 4 running the hottestI'm thinking, this is great we have something to work with, until I've brought the multiplier in.BCLCK Freq: 200 x19Vcore: 1.3vSystem: Stable at one hour run of Prime95Temps: High, 81 degrees towards the end of an hourSo, I've started bringing base clock down gradually until I saw temp decrese, cranked up the DRAM timing and decided to let it run for the rest of the night.BCLCK Freq: 190 x19Vcore: 1.3vDRAM Timings: 7-7-7-24System: Stable, I've hanged around for about 10 minutes before I went to bed, woke up to find out that the box restarted, most likely due to stupid Windows update there was from MS yesterday for Windows7. Inconclusive.Temps: Max 80 degrees at the 10 minute mark when I was leaving, disapointed. Ok, so I guess it looks like I'm going to have to sacrifice .3Ghz of the overclock to keep the temps down, which is a little disapointing since I thought I had an adequate cooling. (Coolermaster CM690 case with 6 fans, one of them directly at the bottom of the CPU area, Thermalright Ultra-120 eXtreme CPU.) It's also possible that the room in the basement was on a little warmer side last night, I think I might be able to get better temps when the outside temps decrease to fall/winter ones here in the midwest.I will resume testing this evening, I just wanted to ask - since I've reached stabil system at 200 base clock, should I keep this clock at 200 and decrease the multiplier or should I do what I've done so far and keep moving the clock down keeping the multiplier at 19?Thanks guys!

I think you'll be able to keep it at 3.8 GHz. Worry not!I know I said to stop when it hits 80, but if it was stable for an hour at 19x200 and never topped 81, it's probably not sustaining that temp and I would leave it there and start tinkering with the VCore. I know that for my particular CPU, 3.8 GHz (21x181) only requires 1.225V. Yours may be different, but I would bet there's some room to knock the voltages down a little bit, which in turn will bring down your temperatures. Push it down in steps of two until it starts giving you blue screens within a few minutes of Prime testing, then go back up about two steps above the last one that worked, and let it run overnight again. If it crashes overnight, don't worry about it, just push it up a little bit and try again.As for your question of whether it's better to lower the multiplier or the base clock, I don't think it matters too much, but the base clock obviously lets you make smaller adjustments. If you have to lower something, I'd suggest lowering that, especially if you plan on using SpeedStep/EIST once you're done. That saves energy by dropping the multiplier, so leaving it at 19 would give it more room to drop and allow for greater energy savings.

Will do! I'll report back either later tonight or tomorrow morning. :)

Will do! I'll report back either later tonight or tomorrow morning. :)

Sounds good. Also, it's worth noting that stress tests like Prime 95 represent an absolute worst-case scenario for CPU load, and most people will never use anything that pushes the CPU nearly as hard. So even if you can't get it below 1.3V (unlikely) and 81 is as hot as it gets under Prime testing, normal load temps will probably rarely exceed 70.

Even a long FSX flight would not heat up CPU that hot?

Nope, mine pushes 80 when I'm testing, and FSX doesn't usually get it higher than upper 60s.

According to the screenshot tutorial you've provided, they're acheiving 4.0Ghz on a very similar system with much lower Vcore voltage of 1.250v versus mine that is set at 1.325v. I will read all this and most likely start from lower base clock like Mike suggested and go up. It's kind of hard to predict now when I'm not around the machine. I will report back either late tonight or some time tomorrow morning. :)

If your i920 CPU is an early one (revision C0/C1) it might be hard to get above 3.8GHz. Some of the C0 920 would OC higher, but not all.

Looks like I'll settle for 19x195 (3.7GHz), it was the most stable and lasted for a whole 10hrs of Prime95 testing without any issues at 81 degrees top. The only thing I did not test was the memory, I will do it tonight.Thanks to everyone who contributed to help me out in this thread, especially Mike.

Not too shabby. Glad I could help!