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yullbarez

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Discussion starter · #1 ·
Hi i'm beginner at overclocking. I've overclocked my Xeon X5450 for 3.48 GHz Voltage 1.2375V with Asus ROG Commando mobo. I've underclocked RAMs 800 MHz to 772 MHz for stability Voltage 1.8V. Then i've tested the CPU stability with using Prime95 for 2 hours. I've done the test without errors. After the test i was working with Dreamweaver for 3 hours i've got that BSOD 'Memory management' and i've got different BSODs. I'm not sure the BSODs are caused by RAM. It could be caused by CPU.
BIOS Settings:
AI Tuning [Manual]
CPU Frequency [386]
DRAM Frequency [DDR2-772MHz]
PCI Express Frequency [100]
PCI Clock Synchronization [Auto]
Spread Spectrum [Disabled]
CPU VCore Voltage [Auto] (it works at 1.2375 V)
FSB Termination Voltage [Auto]
NB VCore [Auto]
Memory Voltahe [1.800V]
DDRII Cannel A REF Voltage [Auto]
DDRII Cannel B REF Voltage [Auto]
DDRII Controller REF Voltage [Auto]
SB VCore(SATA,PCIE) [Auto]
SB Chipset Voltage [Auto]
Asus C.G.I [Disable]
Static Read Control [Disable]
Configure DRAM Timing by SPD [enable]
CPU Configuration:
CPU Ratio Setting [09.0]
C1E Support [Disabled]
Max CPUID Value Limit [Disabled]
Vanderpool Technology [Disabled]
CPU TM Function [Disabled]
Execute Disable Bit [Enable]
SpeedStep [Disable]
There are my bios settings. Is something wrong on bios settings i'll change it.
System Specs:
Intel Xeon X5450 CPU
Asus ROG Commando P965 Chipset Mobo
AMD FirePro V5800 1GB GDDR5 128 Bit GPU
Kingston (4x2gb) 8GB DDR2 800 MHz CL6 RAM
HDD1: Samsung HD155UI 1.5 TB
HDD2: Samsung HD250HJ 250 GB
HDD3: Samsung SP0411N 40 GB
PSU: SilverStone Strider 500W 80+ Bronze
OS: Windows 10 Pro 64-Bit 1809

Sorry for my English.
 
#2 ·
Your overclock settings probably aren't good enough for stability. The main culprit is probably having the core voltage set to Auto. Never, ever, ever, ever, ever, ever use Auto for core voltage when overclocking.

Also, 2 hours in Prime95 is nowhere near enough. It's not about the length of time with Prime95. It's not a constant, unchanging load. If it were, then Prime95 would never be used for this purpose because that would be useless for determining stability. The way Prime95 works is, it does a completely different calculation every 15 minutes. In the Blend test, there are 82 different calculations. You did the first 6 or 7. I know that there are exactly 4 15-minute segments in 2 hours of time, but there are several seconds of time in between each calculation where nothing is happening.

I realize you only raised the clock 480 MHz, but still, you only did the first 6 or 7 calculations (FFTs) in Prime95. To do all 82 would take about 24 hours, and that's why can find a common recommendation of running it for 24 hours. It's not the same as gaming for 24 hours, or doing some other demanding task for 24 hours. It's about putting the system through all of Prime95's various prime calculations to give it a complete test.

But, to simplify this, set your core voltage to Manual or Fixed or whatever your motherboard calls it and set it so that your voltage is at - or higher - the voltage you're seeing with it on Auto. What does CPU-Z say your core voltage is while running Prime95?
 
Discussion starter · #3 · (Edited)
TwoCables said:
Your overclock settings probably aren't good enough for stability. The main culprit is probably having the core voltage set to Auto. Never, ever, ever, ever, ever, ever use Auto for core voltage when overclocking.

Also, 2 hours in Prime95 is nowhere near enough. It's not about the length of time with Prime95. It's not a constant, unchanging load. If it were, then Prime95 would never be used for this purpose because that would be useless for determining stability. The way Prime95 works is, it does a completely different calculation every 15 minutes. In the Blend test, there are 82 different calculations. You did the first 6 or 7. I know that there are exactly 4 15-minute segments in 2 hours of time, but there are several seconds of time in between each calculation where nothing is happening.

I realize you only raised the clock 480 MHz, but still, you only did the first 6 or 7 calculations (FFTs) in Prime95. To do all 82 would take about 24 hours, and that's why can find a common recommendation of running it for 24 hours. It's not the same as gaming for 24 hours, or doing some other demanding task for 24 hours. It's about putting the system through all of Prime95's various prime calculations to give it a complete test.

But, to simplify this, set your core voltage to Manual or Fixed or whatever your motherboard calls it and set it so that your voltage is at - or higher - the voltage you're seeing with it on Auto. What does CPU-Z say your core voltage is while running Prime95?
Click to expand...
That problem when i changed cpu voltage manually system won't boot and i have to reset CMOS. It works 1.2375V. I can't understand why it wouldn't boot after increase the voltage. Even i increase voltage 1.25V it still won't boot. CPU-Z says the voltage 1.456V but AIDA 64 says 1.2375V that's really weird.
 
#4 ·
yullbarez said:
That problem when i changed cpu voltage manually system won't boot and i have to reset CMOS. It works 1.2375V. I can't understand why it wouldn't boot after increase the voltage. Even i increase voltage 1.25V it still won't boot. CPU-Z says the voltage 1.456V but AIDA 64 says 1.2375V that's really weird.
Click to expand...
1.456V is the actual voltage. 1.2375V is the VID, which is not the actual voltage. It's not the current voltage powering the CPU. It's not what you want to look at. You want the CPU core voltage, which is what you are seeing in CPU-Z. 1.456V is clear evidence of why you should avoid Auto voltage. That's an extremely high voltage. Extremely! But, since Auto is setting the voltage that high, you can see now why manually setting it so low doesn't work.

Again, 1.2375V is not your core voltage. Stop looking at that.
 
Discussion starter · #5 · (Edited)
TwoCables said:
1.456V is the actual voltage. 1.2375V is the VID, which is not the actual voltage. It's not the current voltage powering the CPU. It's not what you want to look at. You want the CPU core voltage, which is what you are seeing in CPU-Z. 1.456V is clear evidence of why you should avoid Auto voltage. That's an extremely high voltage. Extremely! But, since Auto is setting the voltage that high, you can see now why manually setting it so low doesn't work.

Again, 1.2375V is not your core voltage. Stop looking at that.
Click to expand...
I know that VID voltage. Should i set BIOS Vcore voltage 1.2375V or higher? I using Hyper Evo 212 Cooler and CPU temp around at 41-49C on stress. But i can't still understand why that core voltage too high. If that core running at 1.456V voltage my cpu cooler couldn't be handle that voltage. I'll try set it 1.2375V manually. I'm didn't try to set voltage at 1.2375 or higher before. I've just tried undervoltage it. CPU Could be handle on it at stock voltage because i've overclocked CPU little more. How to learn stock CPU Core Voltage?
 
#6 ·
yullbarez said:
I know that VID voltage. Should i set BIOS Vcore voltage 1.2375V or higher? I using Hyper Evo 212 Cooler and CPU temp around at 41-49C on stress. But i can't still understand why that core voltage too high. If that core running at 1.456V voltage my cpu cooler couldn't be handle that voltage. I'll try set it 1.2375V manually. I'm didn't try to set voltage at 1.2375 or higher before. I've just tried undervoltage it. CPU Could be handle on it at stock voltage because i've overclocked CPU little more. How to learn stock CPU Core Voltage?
Click to expand...
There are 2 reasons why the temperature isn't all that high with the voltage at 1.456V:


  1. You're using the Blend test in Prime95. I have forgotten that with your CPU (all Intel CPUs from that era), Blend isn't anywhere near as effective at testing stability as the Small FFTs test is - and the Small FFTs test will also make the core temperature much higher for that reason.
  2. Your overclock is only 480 MHz above stock.

So, use the Small FFTs test for that CPU.

Try to drop "1.2375V" from your mind. Stop looking at it, stop considering it, stop thinking about it. It's just the VID. Ignore it. Forget about it, if you can. All you need to watch is the CPU core voltage in CPU-Z.

So, when you set the voltage manually - which is what you have to do when overclocking - start with something that should almost guarantee stability, like say, maybe 1.35V - and then go from there. Again, go by what CPU-Z says your voltage is.

I don't think there is such a thing as the stock voltage. Just focus on overclocking. ;)
 
Discussion starter · #7 ·
TwoCables said:
There are 2 reasons why the temperature isn't all that high with the voltage at 1.456V:


  1. You're using the Blend test in Prime95. I have forgotten that with your CPU (all Intel CPUs from that era), Blend isn't anywhere near as effective at testing stability as the Small FFTs test is - and the Small FFTs test will also make the core temperature much higher for that reason.
  2. Your overclock is only 480 MHz above stock.

So, use the Small FFTs test for that CPU.

Try to drop "1.2375V" from your mind. Stop looking at it, stop considering it, stop thinking about it. It's just the VID. Ignore it. Forget about it, if you can. All you need to watch is the CPU core voltage in CPU-Z.

So, when you set the voltage manually - which is what you have to do when overclocking - start with something that should almost guarantee stability, like say, maybe 1.35V - and then go from there. Again, go by what CPU-Z says your voltage is.

I don't think there is such a thing as the stock voltage. Just focus on overclocking. ;)
Click to expand...
I'll try to set voltage at 1.35V. But i'm scare for pc won't boot. My motherboard have CMOS reset button.
Before i've set RAM voltage to 1.8V it's works at 2.0V i've noticed it and changed 1.8V. Then CPU voltage i was thinking that BIOS setting about VID voltage and now i've learned form you it's a Core voltage. Thank you for helping. :) I'll write after the changed voltage 1.35V.
 
#8 ·
yullbarez said:
I'll try to set voltage at 1.35V. But i'm scare for pc won't boot. My motherboard have CMOS reset button.
Before i've set RAM voltage to 1.8V it's works at 2.0V i've noticed it and changed 1.8V. Then CPU voltage i was thinking that BIOS setting about VID voltage and now i've learned form you it's a Core voltage. Thank you for helping. :) I'll write after the changed voltage 1.35V.
Click to expand...
Problems while overclocking is a part of the process. Don't be scared of problems. A good scientist keeps experimenting until there's success.
 
Discussion starter · #13 ·
TwoCables said:
Progress. :)
Click to expand...
1.4250V still crashing. I've got BSOD's "Memory managment" , "Attempted write to readonly memory" , system service expection. First time i'm getting whea uncorrectable error that BSOD causing by low voltage. Now i'm getting RAM like errors. It crashing browser and causing BSOD. Memory works on 1.8V(DDR2 Stock voltage)
 
#14 · (Edited)
yullbarez said:
1.4250V still crashing. I've got BSOD's "Memory managment" , "Attempted write to readonly memory" , system service expection. First time i'm getting whea uncorrectable error that BSOD causing by low voltage. Now i'm getting RAM like errors. It crashing browser and causing BSOD. Memory works on 1.8V(DDR2 Stock voltage)
Click to expand...
The FSB Termination Voltage and NB VCore might have to be tweaked too. I'm not sure though. I mean remember, I haven't overclocked anything this old in 11 or 12 years.

I had the Gigabyte GA-EP45-UD3P with the E8400. I found my Notepad document for the settings I was using too! I had the CPU Termination (basically the FSB Termination I think) set to 1.280V and I had the MCH Core (NB VCore, pretty much I think) set to 1.280V too.

This will be very confusing, but, I don't know, it might help somehow:

CPU = E8400 E0
VID = 1.2500V
Motherboard = EP45-UD3P (Rev. 1.6)
BIOS Version = FFb
Ram = G.SKILL F2-9600CL5D-4GBPI


MB Intelligent Tweaker(M.I.T.)
Robust Graphics Booster .............: Auto
CPU Clock Ratio .....................: 9X
Fine CPU Clock Ratio.................: -
CPU Frequency .......................: 4.05 GHz


Clock Chip Control
Standard Clock Control
CPU Host Clock Control...............: Enabled
CPU Host Frequency (Mhz) ............: 450
PCI Express Frequency (Mhz) .........: 100 (set manually)


Advanced Clock Control
CPU Clock Drive......................: 800mV
PCI Express Clock Drive..............: 900mV
CPU Clock Skew.......................: 0ps
MCH Clock Skew.......................: 0ps


DRAM Performance Control
Performance Enhance..................: Standard
Extreme Memory Profile (X.M.P.)......: Disabled
(G)MCH Frequency Latch...............: Auto
System Memory Multiplier ............: 2.66D
Memory Frequency (Mhz) ..............: 1200
DRAM Timing Selectable ..............: Manual



Standard Timing Control
CAS Latency Time.....................: 5
tRCD ................................: 5
tRP..................................: 5
tRAS.................................: 15

Advanced Timing Control
tRRD.................................: 3
tWTR.................................: 3
tWR..................................: 6
tRFC.................................: 54
tRTP.................................: 3
Command Rate (CMD) ..................: Auto


Channel A
Static tRead Value...................: 10
Channel B
Static tRead Value...................: 10



Motherboard Voltage Control

CPU
Load Line Calibration (LLC) .........: Disabled
CPU Vcore............................: 1.35000
CPU Termination.....1.200V*..........: 1.280
CPU PLL.............1.500V*..........: 1.590
CPU Reference.......0.760V*..........: Auto

MCH/ICH
MCH Core............1.100V...........: 1.280
MCH Reference.......0.800V...........: 0.720 (so, it's actually 0.770)
MCH/DRAM Ref........0.900V...........: Auto
ICH I/O.............1.500V...........: 1.500
ICH Core............1.100V...........: 1.100

DRAM
DRAM Voltage .........1.800V.........: 2.120 (2.100V in Hardware Monitor)
DRAM Termination .....0.900V.........: Auto
Channel A Reference ..0.900V.........: Auto
Channel B Reference ..0.900V.........: Auto


My memory was rated for 2.1V.

Oh, and I think some of these settings were just what I was told to do by people I saw as the overclocking gods of Overclock.net. lol :)
 
Discussion starter · #15 · (Edited)
NB Voltage at 1.6V and FSB VTT(i'm not sure that FSB termination voltage) 1.344V. But these voltages stock values of my mobo. And it had P965 chipset. Someone hit 4.1 GHz with using my mobo with E5450 that video can found on YT.
These voltage values same like my settings.
 
#16 ·
yullbarez said:
NB Voltage at 1.6V and FSB VTT(i'm not sure that FSB termination voltage) 1.344V. But these voltages stock values of my mobo. And it had P965 chipset. Someone hit 4.1 GHz with using my mobo with E5450 that video can found on YT.
These voltage values same like my settings.
Click to expand...
I would bet they were only able to keep it at 4.1 for an extremely short time.
 
#18 ·
yullbarez said:
I just wanna get 3.6 GHz now. Maybe i would try get higher. I think so but he benchmarked it and not got crashed.
Click to expand...
Was he keeping it at 4.1 GHz 24/7? Or was he just going for the highest possible overclock but could only maintain it for a minute or so?

A lot of people overclock to extremely high extremes for a minute or two, get a CPU-Z validation and/or make a YouTube video to show it off, and then they drop the clock way down so until it's actually stable for normal computer use like gaming and everything else. I would never expect much more than 3.5 to 3.6 GHz stable on a P965 motherboard. I would expect that to be the high end of the possible clock speed.

I have a seemingly random question: what is your memory like? Is it high-end Kingston memory? Or is it the basic naked type with no heatspreaders?
 
Discussion starter · #19 ·
TwoCables said:
Was he keeping it at 4.1 GHz 24/7? Or was he just going for the highest possible overclock but could only maintain it for a minute or so?

A lot of people overclock to extremely high extremes for a minute or two, get a CPU-Z validation and/or make a YouTube video to show it off, and then they drop the clock way down so until it's actually stable for normal computer use like gaming and everything else. I would never expect much more than 3.5 to 3.6 GHz stable on a P965 motherboard. I would expect that to be the high end of the possible clock speed.

I have a seemingly random question: what is your memory like? Is it high-end Kingston memory? Or is it the basic naked type with no heatspreaders?
Click to expand...
A basic naked with no heatspreaders. I'll get Kingston HyperX DDR2 1066 MHz RAM kit on this month.
 
#20 ·
yullbarez said:
A basic naked with no heatspreaders. I'll get Kingston HyperX DDR2 1066 MHz RAM kit on this month.
Click to expand...
Overclocking requires very good memory. Very. That guy on YouTube probably had excellent memory.

He probably also had a great PSU as well, namely one that delivers very stable and accurate power (very low ripple and very tight voltage regulation). Yours is .... ok, but not all that good. I just haven't said anything yet because I always feel bad when I do! I hate telling people their PSU is an obstacle for overclocking or upgrading or whatever the case may be. However, with as much as we keep hitting a wall with overclocking, I think your biggest obstacles are the motherboard, memory, and PSU.
 
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