P55-UD4P Random Reboots

[failcake007]

Hey there,

I've recently assembled a new setup:

Intel Core i7 860
Gigabyte GA-P55-UD4P (rev 1.0) BIOS F8
4GB Corsair Dominator 1600 CMD4GX3M2A1600C8 ( 8-8-8-24 1.65v )
Zalman 9900NT CPU Cooler
Gigabyte Radeon HD5850 OC GV-R5850-1GD
Seagate Barracuda ES2 ST3500320NS 500gb HD
Western Digital Caviar Green 1.5TB WD15EARS
Zalman ZM600-HP 600W PSU
Windows 7 Ultimate 64bit

The problem is that I carry on getting random reboots in Windows. The screen seems to tear slightly then the system reboots itself almost instantly. No BSOD or anything. Sometimes it happens at the login screen, sometimes while watching movies, sometimes while browsing the net, and pretty much always within the first 30 minutes of a prime95 torture test.

I've tried a variety of BIOS settings. The most stable so far (i.e. least numerous resets) seems to be:

Advanced Frequency Settings:

CPU Clock Ratio 21x

Advanced Core Features [Press Enter]:

Intel(R) Turbo Boost Tech................[Enabled]
CPU Cores Enabled........................[All]
CPU Multi-Threading......................[Enabled]
CPU Enhanced Halt (C1E)..................[Disabled]
C3/C6/C7 State Support...................[Disabled]
CPU Thermal Monitor......................[Enabled]
CPU EIST Function........................[Disabled]
Bi-Directional PROCHOT...................[Enabled]

QPI Clock Ratio..........................[x36]
QPI Link Speed........................[6000MHz]
Uncore Clock Ratio....................[18x]
Uncore Frequency.........................3000MHz

>>>>> Standard Clock Control <<<<<

Base Clock (BCLK) Control................[Enabled]
BCLK Frequency ..........................[166]
Extreme Memory Profile (X.M.P.)..........[Disabled]
System Memory Multiplier (SPD)...........[8]
Memory Frequency (MHz)................1333
PCI Express Frequency (MHz)..............[100]
C.I.A.2..................................[Disabled]

>>>>> Advanced Clock Control <<<<<

CPU Clock Drive..........................[ 800mV]
PCI Express Clock Drive..................[ 900mV]
CPU Clock Skew...........................[ 0ps]

Advanced Memory Settings:

Extreme Memory Profile (X.M.P.)..........[Disabled]
System Memory Multiplier (SPD)...........[8.0]
Memory Frequency (MHz)................1333
Performance Enhance (SPD)............. [Standard]
DRAM Timing Selectable (SPD)............ [Quick]
Profile DDR Voltage ..................1.5v
Profile QPI Voltage ..................1.1v
Channel Interleaving.....................[Auto]
Rank Interleaving........................[Auto]

>>>>> Channel A & B

Channel A Timing Settings [Press Enter]:
Cas Latency Time........................[8]
tRCD....................................[8]
tRP.....................................[8]
tRAS...................................[24]

>>>>> Advanced Timing Control

tRC....................................[Auto]
tRRD...................................[Auto]
tWTR...................................[Auto]
tWR....................................[Auto]
tWTP...................................[Auto]
tWL....................................[Auto]
tRFC...................................[Auto]
tRTP...................................[Auto]
tFAW...................................[Auto]
Command Rate (CMD).................. 1 [2]

>>>>> Misc Timing Control

B2B Cas Delay..........................[Auto]
Round Trip Latency.....................[Auto]

Channel A Turnaround Settings [Press Enter]:
Different DIMMs........................[Auto]
Different DIMMs........................[Auto]
On The Same Rank.......................[Auto]

>>>>> Channel A Writes Followed By Writes

Different DIMMs........................[Auto]
Different DIMMs........................[Auto]
On The Same Rank.......................[Auto]


Advanced Voltage Settings:

******Mother Board Voltage Control ******
Voltage Types............Normal......Current
--------------------------------------------

>>> CPU
Load Line Calibration...................[Enabled]
CPU Vcore..................1.19375v..[1.30v]
QPI/VTT Voltage..........1.100v.....[1.35v]

>>> MCH/ICH
PCH Core....................1.050v.....[1.140v]
CPU PLL......................1.800v.....[1.880v]

>>> DRAM
DRAM Voltage..............1.500v.....[1.660v]
DRAM Termination.........0.750v.....[Auto]
Ch-A Data VRef............0.750v.....[Auto]
Ch-A Data VRef............0.750v.....[Auto]
Ch-B Data VRef............0.750v.....[Auto]
Ch-B Data VRef............0.750v.....[Auto]


Miscellaneous Settings:[/SIZE]

Isochronous Support....................[Enabled]
Virtualisation technology..............[Enabled]
USB Storage Detect ....................[Disabled]

I let memtest run this morning while I was out. Ran for +- 6 hours, 11 passes, 0 errors, so I'm quite sure it's not a memory problem. I've reset my BIOS to optimised defaults for the mean time, and changed memory performance enhance to standard. Ran 4 passes of memtest with 0 errors, but still getting reboots in Windows. I also removed the CPU and checked the socket for bent pins, cause I'd read that this was a common issue with the LGA-1156 socket, but all the pins were fine.

All drivers are up to date, and I've flashed the BIOS to latest (F8). I'm running out of ideas here... I've attached the minidump from my last crash if anyone cares to take a look.

Thanks and any help would be much appreciated.

[warren300]

Re: P55-UD4P Random Reboots

cant see anything wrong with your settings,have you tried with normal cpu voltage setting?? 1.3v seems a little high for 3.4ghz clock

[failcake007]

Re: P55-UD4P Random Reboots

Lowest I've tried with is 1.25. With turbo mode it clocks up to 3.65 Ghz, so 1.3v doesn't seem excessive. Just tried running Everest stress test. It fails within a few seconds with: "Warning: Hardware failure detected! Test stopped". Is there any way to find out which component caused the error?

[warren300]

Re: P55-UD4P Random Reboots

its better to use as less a voltage as you can while still being 100% stable,i can clock to 3.8ghz with 1.18750,you might need a few clicks more qpi voltage to be 100% stable,its likely not enough qpi/vtt voltage when it randomly reboots or blue screens.dont go any higher than 1.3800 you wont need much for 3.4-3.6ghz.too much voltage can cause instability too

[JureZ]

Re: P55-UD4P Random Reboots

Hey there,

I've recently assembled a new setup:

Intel Core i7 860
Gigabyte GA-P55-UD4P (rev 1.0) BIOS F8
4GB Corsair Dominator 1600 CMD4GX3M2A1600C8 ( 8-8-8-24 1.65v )
Zalman 9900NT CPU Cooler
Gigabyte Radeon HD5850 OC GV-R5850-1GD
Seagate Barracuda ES2 ST3500320NS 500gb HD
Western Digital Caviar Green 1.5TB WD15EARS
Zalman ZM600-HP 600W PSU
Windows 7 Ultimate 64bit

The problem is that I carry on getting random reboots in Windows. The screen seems to tear slightly then the system reboots itself almost instantly. No BSOD or anything. Sometimes it happens at the login screen, sometimes while watching movies, sometimes while browsing the net, and pretty much always within the first 30 minutes of a prime95 torture test.

I've tried a variety of BIOS settings. The most stable so far (i.e. least numerous resets) seems to be:
...

I let memtest run this morning while I was out. Ran for +- 6 hours, 11 passes, 0 errors, so I'm quite sure it's not a memory problem. I've reset my BIOS to optimised defaults for the mean time, and changed memory performance enhance to standard. Ran 4 passes of memtest with 0 errors, but still getting reboots in Windows. I also removed the CPU and checked the socket for bent pins, cause I'd read that this was a common issue with the LGA-1156 socket, but all the pins were fine.

All drivers are up to date, and I've flashed the BIOS to latest (F8). I'm running out of ideas here... I've attached the minidump from my last crash if anyone cares to take a look.

Thanks and any help would be much appreciated.

At this time I see that the BCLK is at default 166, no overclocking.
here are my suggestions:


BCLK Frequency ..........................[166] this is the default clock, no overclock

System Memory Multiplier (SPD)...........[8] OK
Memory Frequency (MHz)................1333 OK

Uncore Clock Ratio....................[18x] change to x16 or x 17 ( 2x or 2x+1 the memory clock multiplier)

CPU Vcore..................1.19375v..[1.30v] no need to increase without overclock, maybe use 1.20V ?
QPI/VTT Voltage..........1.100v.....[1.35v] no need to increase without overclock, , maybe use 1.15V ?

DRAM Voltage..............1.500v.....[1.660v] OK


You do not say much about your system temperatures.
The excess voltages may be the cause of overheating.

Also, the video card may be causing the crashes if you are over clocking it.

I guess that you want the system to be stable first at standard clock, and overclock after wards?

Good luck, Jure Z.

[failcake007]

Re: P55-UD4P Random Reboots

133 is the default bclk. I overclocked it up to 166Mhz, as that seemed to get it more stable by allowing me to drop the mem multiplier. I later set it back down to 133 to try to get it stable at default clocks, but to no avail. Sorry for the confusion. I'm now back to 166Mhz bclk. Guess it would make sense trying to get it stable at default clocks first, and then overclock from there, but as I say, I seem to be getting more stable results when overclocking.

Temperatures do not seem to be a problem. At default settings max temp is 52 on Core 1 with realtemp, other cores are all around 48-49. At 1.3v the temps go up to 72 on Core 1, and the others hover around 65-68.

The video card has a factory overclock of 765Mhz (from 725), but I have not tinkered with it from there.

I lowered the core voltage as warren suggested. Both 1.2v and 1.23125(default) crashed the PC while loading startup programs. Also bumped the QPI up to 1.37v (highest it can go without going over 1.38v).

How can I changed the Uncore Clock Ratio? Mine seems fixed (grayed out)...

[warren300]

Re: P55-UD4P Random Reboots

i dont think you can change uncore clock ratio on p55 boards,some other users were unstable because c1e and c3/c6/c7 states were enabled in bios advanced cpu features..but you wont be able to use turbo without c3/c6/c7 enabled so youll have to raise bclk slightly to compensate...just try with both c1e and c3...disabled and see if it still crashes if it does then re enable them if not keep disabled and raise bclk

[failcake007]

Re: P55-UD4P Random Reboots

I think I've got it sorted now. Didn't realise that you can't use turbo mode with c3/c6/c7 disabled. I already had C1E and C3/C6/C7 disabled, so I disabled turbo, and all seems to be working now at stock clocks and voltages. Been running Everest stability test for 30mins now, and no reset or BSOD, which is a first

Will leave it over night, and if it stays stable, will start overclocking. Current settings are:


Advanced Frequency Settings:

CPU Clock Ratio 21x

Advanced Core Features [Press Enter]:

Intel(R) Turbo Boost Tech................[Disabled]
CPU Cores Enabled........................[All]
CPU Multi-Threading......................[Enabled]
CPU Enhanced Halt (C1E)..................[Disabled]
C3/C6/C7 State Support...................[Disabled]
CPU Thermal Monitor......................[Enabled]
CPU EIST Function........................[Disabled]
Bi-Directional PROCHOT...................[Enabled]

QPI Clock Ratio..........................[36x]
QPI Link Speed........................[4.8GHz]
Uncore Clock Ratio....................[18x]
Uncore Frequency.........................2400MHz

>>>>> Standard Clock Control <<<<<

Base Clock (BCLK) Control................[Enabled]
BCLK Frequency ..........................[133]
Extreme Memory Profile (X.M.P.)..........[Disabled]
System Memory Multiplier (SPD)...........[10.0]
Memory Frequency (MHz)................1333
PCI Express Frequency (MHz)..............[100]
C.I.A.2..................................[Disabled]

>>>>> Advanced Clock Control <<<<<

CPU Clock Drive..........................[ 800mV]
PCI Express Clock Drive..................[ 900mV]
CPU Clock Skew...........................[ 0ps]

Advanced Memory Settings:

Extreme Memory Profile (X.M.P.)..........[Disabled]
System Memory Multiplier (SPD)...........[10.0]
Memory Frequency (MHz)................1333
Performance Enhance (SPD)............. [Standard]
DRAM Timing Selectable (SPD)............ [Quick]
Profile DDR Voltage ..................1.5
Profile QPI Voltage ..................1.1
Channel Interleaving.....................[Auto]
Rank Interleaving........................[Auto]

>>>>> Channel A & B

Channel A Timing Settings [Press Enter]:
Cas Latency Time........................[8]
tRCD....................................[8]
tRP.....................................[8]
tRAS...................................[24]

>>>>> Advanced Timing Control

tRC....................................[Auto]
tRRD...................................[Auto]
tWTR...................................[Auto]
tWR....................................[Auto]
tWTP...................................[Auto]
tWL....................................[Auto]
tRFC...................................[Auto]
tRTP...................................[Auto]
tFAW...................................[Auto]
Command Rate (CMD).................. 1 [2]

>>>>> Misc Timing Control

B2B Cas Delay..........................[Auto]
Round Trip Latency.....................[Auto]

Channel A Turnaround Settings [Press Enter]:
Different DIMMs........................[Auto]
Different DIMMs........................[Auto]
On The Same Rank.......................[Auto]

>>>>> Channel A Writes Followed By Writes

Different DIMMs........................[Auto]
Different DIMMs........................[Auto]
On The Same Rank.......................[Auto]


Advanced Voltage Settings:

******Mother Board Voltage Control ******
Voltage Types............Normal......Current
--------------------------------------------

>>> CPU
Load Line Calibration...................[Enabled]
CPU Vcore..................1.19375v..[1.20000v]
QPI/VTT Voltage..........1.100v.....[1.150v]

>>> MCH/ICH
PCH Core....................1.050v.....[1.120v]
CPU PLL......................1.800v.....[1.860v]

>>> DRAM
DRAM Voltage..............1.500v.....[1.660v]
DRAM Termination.........0.750v.....[Auto]
Ch-A Data VRef............0.750v.....[Auto]
Ch-A Data VRef............0.750v.....[Auto]
Ch-B Data VRef............0.750v.....[Auto]
Ch-B Data VRef............0.750v.....[Auto]


Miscellaneous Settings:[/SIZE]

Isochronous Support....................[Enabled]
Virtualisation technology..............[Enabled]
USB Storage Detect ....................[Disabled]</pre>

[warren300]

Re: P55-UD4P Random Reboots

try with c3/c6/c7 and turbo enabled and see if its stable,maybe not having c3 enabled made it unstable?

[JureZ]

Re: P55-UD4P Random Reboots

I think I've got it sorted now. Didn't realize that you can't use turbo mode with c3/c6/c7 disabled. I already had C1E and C3/C6/C7 disabled, so I disabled turbo, and all seems to be working now at stock clocks and voltages. Been running Everest stability test for 30mins now, and no reset or BSOD, which is a first

Will leave it over night, and if it stays stable, will start overclocking. Current settings are:


Advanced Frequency Settings:

...

Glad to see you made so much progress!

two things I noticed perusing the manual for your MOBO:

<link rel="File-List" href="file:///C:%5CDOCUME%7E1%5CJure%5CLOCALS%7E1%5CTemp%5Cmsoht ml1%5C01%5Cclip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <w:DontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><style> <!-- /* Font Definitions */ @font-face {font-family:"Arial Narrow"; panose-1:2 11 5 6 2 2 2 3 2 4; mso-font-alt:"Arial Narrow"; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:647 2048 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} p.Pa3, li.Pa3, div.Pa3 {mso-style-name:Pa3; mso-style-next:Normal; margin:0in; margin-bottom:.0001pt; mso-line-height-alt:9.05pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:"Arial Narrow"; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";} p.Pa20, li.Pa20, div.Pa20 {mso-style-name:Pa20; mso-style-next:Normal; margin:0in; margin-bottom:.0001pt; mso-line-height-alt:8.05pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:"Arial Narrow"; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> <o:p>1) Uncore ratio may not be changed...
</o:p>

Uncore Clock Ratio : Displays the Uncore clock ratio. (This ratio is fixed.)

2) You may look for advanced / hidden features in the MIT menu, maybe you find something interesting...

<link rel="File-List" href="file:///C:%5CDOCUME%7E1%5CJure%5CLOCALS%7E1%5CTemp%5Cmsoht ml1%5C01%5Cclip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <w:DontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><style> <!-- /* Font Definitions */ @font-face {font-family:"Arial Narrow"; panose-1:2 11 5 6 2 2 2 3 2 4; mso-font-alt:"Arial Narrow"; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:647 2048 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} p.Pa8, li.Pa8, div.Pa8 {mso-style-name:Pa8; mso-style-next:Normal; margin:0in; margin-bottom:.0001pt; mso-line-height-alt:8.05pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:"Arial Narrow"; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";} p.Pa20, li.Pa20, div.Pa20 {mso-style-name:Pa20; mso-style-next:Normal; margin:0in; margin-bottom:.0001pt; mso-line-height-alt:8.05pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:"Arial Narrow"; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]-->

While in a submenu, press {<f1>F1} to display a help screen (General Help) of function keys available for the menu. Press <esc> <esc> {ESC} to exit the help screen. Help for each item is in the Item Help block on the right side of the submenu.<o:p></o:p></esc></esc></f1>
If you do not find the settings you want in the Main Menu or a submenu, press <ctl><ctrl>{Ctrl}+{F1}<f1><f1> to access more advanced options.</f1></f1></ctrl></ctl>

good luck, Jure Z.

[Lsdmeasap]

Re: P55-UD4P Random Reboots

So all sorted now?

If so great, glad you found the problem!

[failcake007]

Re: P55-UD4P Random Reboots

Seems to be sorted. Ran stable overnight. I'm sure it's something to do with having turbo enabled with C3/C6/C7 disabled. Under these conditions my processor was still increasing the multiplier to x22, and I'm guessing that it was causing my instability.

I'm gonna try re-enable C3 and turbo, like Warren suggested, but if it doesn't stay stable I'll just disable them again. Will then try some overclocking. Will post my results.

Thanks for all the help guys.

[Lsdmeasap]

Re: P55-UD4P Random Reboots

OK, let us know how your testing goes when you get time to look into that.

[failcake007]

Re: P55-UD4P Random Reboots

Enabling both C3/C6/C7 and turbo seemed to work fine. Disabled them for overclocking though. Decided 3.8Ghz was a decent mark to aim for. I started by setting vcore to 1.3v and qpi to 1.35v, set bclk to 181MHz, loosened the memory timings to 9-9-9-24 and then tinkered with a bunch of the settings till I got it stable. Funnily enough, moving the bclk to 182MHz seemed to help. Once I got it stable, I started reducing the voltages. Currently stable with the following settings:


Advanced Frequency Settings:

CPU Clock Ratio 21x

Advanced Core Features [Press Enter]:

Intel(R) Turbo Boost Tech................[Disabled]
CPU Cores Enabled........................[All]
CPU Multi-Threading......................[Enabled]
CPU Enhanced Halt (C1E)..................[Disabled]
C3/C6/C7 State Support...................[Disabled]
CPU Thermal Monitor......................[Enabled]
CPU EIST Function........................[Disabled]
Bi-Directional PROCHOT...................[Enabled]

QPI Clock Ratio..........................[x36]
QPI Link Speed........................[6.55GHz]
Uncore Clock Ratio....................[18x]
Uncore Frequency.........................3276MHz

>>>>> Standard Clock Control <<<<<

Base Clock (BCLK) Control................[Enabled]
BCLK Frequency ..........................[182]
Extreme Memory Profile (X.M.P.)..........[Disabled]
System Memory Multiplier (SPD)...........[8.0]
Memory Frequency (MHz)................1456
PCI Express Frequency (MHz)..............[100]
C.I.A.2..................................[Disabled]

>>>>> Advanced Clock Control <<<<<

CPU Clock Drive..........................[ 800mV]
PCI Express Clock Drive..................[ 900mV]
CPU Clock Skew...........................[ 0ps]

Advanced Memory Settings:

Extreme Memory Profile (X.M.P.)..........[Disabled]
System Memory Multiplier (SPD)...........[8.0]
Memory Frequency (MHz)................1456
Performance Enhance (SPD)............. [Standard]
DRAM Timing Selectable (SPD)............ [Quick]
Profile DDR Voltage ..................1.5v
Profile QPI Voltage ..................1.1v
Channel Interleaving.....................[Auto]
Rank Interleaving........................[Auto]

>>>>> Channel A & B

Channel A Timing Settings [Press Enter]:
Cas Latency Time........................[9]
tRCD....................................[9]
tRP.....................................[9]
tRAS...................................[24]

>>>>> Advanced Timing Control

tRC....................................[Auto]
tRRD...................................[Auto]
tWTR...................................[Auto]
tWR....................................[Auto]
tWTP...................................[Auto]
tWL....................................[Auto]
tRFC...................................[Auto]
tRTP...................................[Auto]
tFAW...................................[Auto]
Command Rate (CMD).................. 1 [2]

>>>>> Misc Timing Control

B2B Cas Delay..........................[Auto]
Round Trip Latency.....................[Auto]

Channel A Turnaround Settings [Press Enter]:
Different DIMMs........................[Auto]
Different DIMMs........................[Auto]
On The Same Rank.......................[Auto]

>>>>> Channel A Writes Followed By Writes

Different DIMMs........................[Auto]
Different DIMMs........................[Auto]
On The Same Rank.......................[Auto]


Advanced Voltage Settings:

******Mother Board Voltage Control ******
Voltage Types............Normal......Current
--------------------------------------------

>>> CPU
Load Line Calibration...................[Enabled]
CPU Vcore..................1.19375v..[1.22500v]
QPI/VTT Voltage..........1.100v.....[1.350v]

>>> MCH/ICH
PCH Core....................1.050v.....[1.050v]
CPU PLL......................1.800v.....[1.800v]

>>> DRAM
DRAM Voltage..............1.500v.....[1.660v]
DRAM Termination.........0.750v.....[Auto]
Ch-A Data VRef............0.750v.....[Auto]
Ch-A Data VRef............0.750v.....[Auto]
Ch-B Data VRef............0.750v.....[Auto]
Ch-B Data VRef............0.750v.....[Auto]


Miscellaneous Settings:[/SIZE]

Isochronous Support....................[Enabled]
Virtualisation technology..............[Enabled]
USB Storage Detect ....................[Disabled]

Everything seems to be completely stable. Memtest 4 passes no errors, prime95 2 hours no errors, 3DMark06 22746. All in all quite pleased with the outcome.

Anyway, thanks again guys.

[Lsdmeasap]

Re: P55-UD4P Random Reboots

Looks good!

To ensure 100% stability you should test longer with Prime95 and or other tools as well, but I am sure you know that.

Good luck with further testing, and if you need help feel free to let us know.

Command Rate 2? Would 1 not work?