X48 Rampage Formula Preview.

[Alien Grey]

The information from Zucker2k, mikeyakame, A_Grey, and others has been a great help in reducing the blue screen occurrences on my friends system at 4Ghz. Yet the blue screens refuse to go away, I need some input.

Goal: 4GHz using the max multiplier of 8.5 and run ram at 1:1.
system specs:
Bios listed below

Xeon X3360 (Q9550) C1 water cooled with a stock fuzion v2 along with EK northbridge wb, laing D5 @ speed 5, and PA120.3 in one loop. Prime temps are 58C, LinX are 67C, northbridge temp is about 30C.

second loop is EK mosfet wb, 2 EK FC-R600 HD 2900XT crossfire, laing D5 @ speed 5, and PA120.3. The south bridge is heatsinked with a low profile copper sink, it stays in the high 30C.

Video cards are a mismatched crossfire of HD2900XT 1GB and HD2900XT 512mb, both water cooled. Blue screens happen with or without crossfire on.

Ram is 2X2GB GSkill F2-8800CL5GBPI (DDR2 1100) in the blue slots, Vista 64bit Ultimate SP1 all patched up. Jmicron controller is disabled, all sata AHCI installed. Power supply is a Silverstone OP-1000 1Kw. The motherboard is a X48 Rampage Formula.

So the problem is windows blue screens saying "A clock interrupt was not received on a secondary processor within an allocated time" or "General hardware fault". This has been going on for months, and thanks to this thred, it usually happens once or twice a day now. The information about AGTL+ bus signaling, GTL ref, bios 803, cpu clock skew, and Zuckers BIOS, decreased blue screens alot.

Memtest can run all day without errors, and processor has primed for 6 hours no errors, no blue screens. The blue screens very rarely occure under heavy load from gaming or priming, only once that I can remember. They occur during idle desktop, internet browsing, and word documents. Never had any issues during windows load screen.

The CMOS was cleared befor and after flashing the bios, and profiles where re-entered and saved by hand.

Load line calibration is enabled, and tested fine. CPUZ and Everest show no Vcore fluctuations between idle and load. The Vcore stays at 1.360v all the time no matter the load. The board was vdroop pencil moded and sealed by tape during inital building.

NB voltage has been up to 1.73v, SB 1.5v to 1.55v, PL 10 and 9, ai clock twister, all GTL's that fit have been tested, with no improvement and returned to as stated below.

Anyone have any input on settings or experience with thies blue screens?
If the GTL ref are kept within 0.8 to 1.0, is the 1.4 volt max safe FSB termination voltage still valid for long term daily use?

Is it a real ASUS Rampage Formula board?

Whjen it's a real ASUS Rampage Formula board try this.

Use Ai Clock Twister Moderate. DRAM at 1130MHz (DRAM Voltage around 1.94V in BIOS - Mikeyakame should know what Voltage for 1130MHz) tRD 7.

Lower NB Voltage. I don't think you need 1.65V for FSB 471.
I'm using 1.47V (1.45V real) at the moment in the BIOS for FSB 475MHz.

Do you need higher CPU PLL than 1.50V in the BIOS? I'm still using 150V for 3.8GHz 8 X 475MHz.

FSB Termination Voltage is a tricky one. With +1.4V real it's probably to high. I'm using 1.36V (1.26V real) for 3.8GHz 8 X 475MHz.

Try with CPU GTL Voltage reference 0.63X.

CPU Clock Skew and NB Clock Skew should be equal or CPU Clock Skew 100ps more delayed. With a delay of 200ps for the CPU and normal for NB it's probably not good.

Try LLC Disabled. You need higher idle voltage but you won't kill the CPU like that.

LLC is still something I don't understand how it works. I can use LLC Enabled with my Pentium D 840 up to 4.2GHz without problems. Could try higher Clocks but the CPU temperature reaches 70° Celsius under water with CPU Voltage 1.48V.
It runs great with LLC Enabled with my Q9450 at stock speeds. Overclocking my Q9450 with LLC Enabled is a total disaster. I have no idea what is wrong and it gets worse with every new BIOS Update. I can't stay 1 minute stable in Windows XP X64.
I'm not really sure but I think it has something to do with the PCIE and my Graphics Card. At first video signal disappears and a few seconds later my system reboots. It has nothing to do with the CPU Voltage or any other voltage setting.
I've asked the ASUS Global Tech Support to look what could be the problem but I don't get an answer back. It should be easier for them to try to find out what is going on when I enable LLC but I don't think that they care.