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System boots at 21x190MHz, but not at 19x200MHz. How come?

346 Views 7 Replies 5 Participants Last post by  FSF-Foxhound, 
A
CPU: Intel Core i7 920 (C0)
MB: ASUS P6T Deluxe V2 (BIOS 0704)
RAM: OCZ3P1600LV6GK

With 21x190MHz (3990MHz) I'm able to POST, boot Windows and run a wee bit of Prime95 before a BSOD turns up.

If I try 19x200MHz (3800MHz), the system won't even POST. Black screen, not even a beep.

How come? What is limiting my FSB? Can't be the CPU, since it's actually running at a lower speed when I try 19x200MHz, right?

Speed settings:
RAM: 8x (1520MHz when using 190MHz, 1600MHz when using 200MHz)
Uncore: 16X (3040MHz when using 190MHz, 3200MHz when using 200MHz)
QPI: 18X (6840T/s when using 190MHz, 7200T/s when using 200MHz)

RAM latency settings: 7-7-7-24-5-60-8-5 1N

Voltage Settings:
vCore: 1.4v
QPI: 1.35v
PLL: 1.88v
IOH: 1.2v
ICH: 1.2v
DRAM: 1.66v

C1E, Turbo, SpeedStep, HT and Spread Spectrum disabled
LLC enabled
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D
Quote:

Originally Posted by agitator View Post
CPU: Intel Core i7 920 (C0)
MB: ASUS P6T Deluxe V2 (BIOS 0704)
RAM: OCZ3P1600LV6GK

With 21x190MHz (3990MHz) I'm able to POST, boot Windows and run a wee bit of Prime95 before a BSOD turns up.

If I try 19x200MHz (3800MHz), the system won't even POST. Black screen, not even a beep.

How come? What is limiting my FSB? Can't be the CPU, since it's actually running at a lower speed when I try 19x200MHz, right?

Speed settings:
RAM: 8x (1520MHz when using 190MHz, 1600MHz when using 200MHz)
Uncore: 16X (3040MHz when using 190MHz, 3200MHz when using 200MHz)
QPI: 18X (6840T/s when using 190MHz, 7200T/s when using 200MHz)

RAM latency settings: 7-7-7-24-5-60-8-5 1N

Voltage Settings:
vCore: 1.4v
QPI: 1.35v
PLL: 1.88v
IOH: 1.2v
ICH: 1.2v
DRAM: 1.66v

C1E, Turbo, SpeedStep, HT and Spread Spectrum disabled
LLC enabled
it is possible that you have stumbled apon an fsb hole, but I think it might be your NB needing more volts, but dont base that on me lol I havent got an i7
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Lome_Wolf236
the answer is simple: the higher your Baseclock is, the harde it is to get it stable (== more volts)
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A
More of what kind of volts? vCore? QPI? DRAM?
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A
Change QPI/Vtt volts back to default.
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A
What is default for QPI, besides Auto? According to ASUS TurboV, QPI is set to 1.375v when system is running everything on default...I thought 1.375v was too high.
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A
Quote:

Originally Posted by agitator View Post
What is default for QPI, besides Auto? According to ASUS TurboV, QPI is set to 1.375v when system is running everything on default...I thought 1.375v was too high.
its different from CPU to CPU, but usually around 1.15-1.2.

Mine is 1.12.
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F
Your PLL is too high for the 19 multi probably. Set it to 1.6 or something lower.
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