Skylake system stuck at 800mhz

[PaulDoyle333]

I recently build a new system with a i5 6500 ,MSI B150 Gaming M3 board . System has been running fine the last 3 months , last week I felt my mouse become real sluggish all of a sudden and a small red L.E.D turns on at the bottom of the board and drops the CPU to 800mhz . I have spent days troubleshooting the issue and have got to the bottom of it (Well Kind of)

 

This post is for anyone who might be having same issue as i could not find much on the internet about the problem . I tested the system with different PSU , RAM , HDD and fresh OS installs and problem still persisted . I had narrowed it down to motherboard or CPU . I re-seated CPU and checked if maybe there was damaged pins but everything looked perfect . The problem is completely random the system has never crashed and can go days of  gaming with out a problem and then all of sudden randomly it will drop to 800mhz and RED LED on motherboard turns on .Temps are not a issue CPU never hits over 50c  .Here is were it gets strange after some digging around forums I discovered a way to fix the issue although it is not ideal . It seems a feature called "BD PROCHOT" is what is causing the problem it is telling my CPU it or something is to hot and making the CPU downclock to 800mhz . I installed throttlestop and unchecked BD PROCHOT and it instantly fixes the issue . The system has passed a 48hour stress test and runs perfect but only when throttlestop is enabled I have checked all the temps are perfect too . I believe there is a sensor or something on the motherboard that is faulty and causing the CPU to downclock . There is a tiny switch on the motherboard called slow mode it is apparently used for LN2 overclocking' it drops the CPU to 800mhz in case of booting issues.I wish it was as simple as flicking a switch to fix my issue but unfortunately not 'my system will go hours running perfect and all of a sudden it's like that slow mode feature activates itself 'why that feature is on a B150 motherboard is beyond me but it is probably what is causing the issue . 

 

Also the max turbo speed of my i5 6500 is 3.6ghz but when using the throttlestop fix for the 800mhz problem i am seeing my CPU jump up to 3.8 on one core . 

 

This is the strangest system I have ever built and has pissed me off so much . 

 

I think i will stick with Asus boards in the future .

 

Below are pics of system and and RED LED on motherboard , also screenshots of the 800mhz problem and the locked skylake 6500 running at 3.8ghz . 

 

Did anyone ever have anything like this happen to them i have built many many systems over the last 3 years and never ran into this issue . 

[r1Ns3]

Try going to windows and changing your power saving settings. Set it to balanced, then run a stress test and see if the core clock starts going up and down.

Balanced power setting makes it so that if you are idling the cpu does not run at full clock speed, and voltage.

 

But when you launch a game or stress test, it will ramp up the clock speed and voltages. Try that.

If that did not work set it to performance mode instead of balanced. This will run the CPU and it's highest possible clock and voltage at all times.

[vanished]

You are looking for this screen specifically:

Make sure it's set to 100% at max, and "active" for that matter

[PaulDoyle333]

Try going to windows and changing your power saving settings. Set it to balanced, then run a stress test and see if the core clock starts going up and down.

Balanced power setting makes it so that if you are idling the cpu does not run at full clock speed, and voltage.

 

But when you launch a game or stress test, it will ramp up the clock speed and voltages. Try that.

If that did not work set it to performance mode instead of balanced. This will run the CPU and it's highest possible clock and voltage at all times.

Sorry i should of mentioned that was the first thing I tried that is also not the issue . All my pc's are always set at high performance mode , I tried flashing 4 different bios that is available since the boards release and they all have the same issue . The Red L.E.D will fade on and off randomly once that red led comes on there is no way to get the CPU to go over 800mhz without disabling BD PROCHOT in throttlestop

[vanished]

Sorry i should of mentioned that was the first thing I tried that is also not the issue . All my pc's are always set at high performance mode , I tried flashing 4 different bios that is available since the boards release and they all have the same issue . The Red L.E.D will fade on and off randomly once that red led comes on there is no way to get the CPU to go over 800mhz without disabling BD PROCHOT in throttlestop

Regardless of your power mode, something could have still gone wrong - please check the window I posted above to confirm that you are set to 100% and not 5% or something like that.

 

If that really is all fine, then it's time to try changing C-states in the BIOS

[PaulDoyle333]

It can happen right in the middle of a game once the red light is on the CPU just tanks . It  will even report 0.80ghz in the BIOS with 0 drives attached to the system 

[r1Ns3]

It can happen right in the middle of a game once the red light is on the CPU just tanks . It  will even report 0.80ghz in the BIOS with 0 drives attached to the system 

Thermal throttling? I have no clue this seems very fishy.

[PaulDoyle333]

Disabled C states ,disabled intel speedstep ,i even disabled CPU thermal limit .  

[vanished]

Disabled C states ,disabled intel speedstep ,i even disabled CPU thermal limit .  

And no luck?  Hm... I'm out of ideas for the moment

 

(I'm assuming you did check the power options as I mentioned to make sure Windows isn't holding it back)

[PaulDoyle333]

Thermal throttling? I have no clue this seems very fishy.

Nope CPU is nice and cool never gets over 50c . VRM's and chipset are not over heating and system passed a 48hour stress test when i disabled BD PROCHOT in Throtlestop program . Im going pick up a Cheap h110 board just to test as i'm pretty sure its the mobo . I have tested the whole system with different ram different psu . Problem even exist when 0 drives are connected to system . I cleared C-MOS , loaded optimized defaults ect . I have tried everything . I just thought i share the issue as i have never had a issue like this before . Kinda sick i sold my Ivy bridge system to build this one . The only reason i picked a MSI board was because of the color scheme lol (Derp)

[PaulDoyle333]

And no luck?  Hm... I'm out of ideas for the moment

 

(I'm assuming you did check the power options as I mentioned to make sure Windows isn't holding it back)

As i said when 0 HardDrives are attached to PC and it has no operating system running on it the problem is still there so changing any of windows power management features has 0 effect . Thanks for the suggestion anyway but I assure you that was the very first thing i checked when I first noticed the issue last week . 

[vanished]

As i said when 0 HardDrives are attached to PC and it has no operating system running on it the problem is still there so changing any of windows power management features has 0 effect . Thanks for the suggestion anyway but I assure you that was the very first thing i checked when I first noticed the issue last week . 

Fair enough.  I thought the same thing too (that if it does it with no disks it's not a windows problem) but you never specifically said you checked that, so I thought I would make sure since I have seen that solve the problem several times before

[PaulDoyle333]

Fair enough.  I thought the same thing too (that if it does it with no disks it's not a windows problem) but you never specifically said you checked that, so I thought I would make sure since I have seen that solve the problem several times before

No problem at all thanks for your suggestions . I'm at the stage now i'm just gonna use the throttlestop fix and torture the PC for the next week and see if i notice any issues if not my son can have it it will give me a excuse to tell the misses i need a upgrade .

[unclewebb]

BD PROCHOT stands for bi-directional processor hot.  This allows other sensors on your motherboard to signal the CPU which forces the CPU to use the minimum multiplier (8).  The CPU behaves exactly the same as if it was thermal throttling but in this case, the CPU temperature is fine.  On some motherboards, it can be either a temperature switch from the voltage regulator or a power consumption switch.  On your motherboard, it is very likely that the Slow Mode switch intended for LN2 users is failing.  The only fix is a new board.  This problem has nothing to do with Windows.  

 

ThrottleStop is the only free software available that lets a user disable the BD PROCHOT signal path.  When you uncheck BD PROCHOT, that blocks signals from the defective switch getting to your CPU.  A simple fix and after you disable BD PROCHOT, you should be able to exit ThrottleStop and the BD PROCHOT signal path will remain disabled.  ThrottleStop also has an option that you can add to the INI configuration file.

 

ExitTime=5

 

This option tells ThrottleStop to exit 5 seconds after it starts.  ThrottleStop will start up, fix the problem and then quietly exit.

 

Why is ThrottleStop "not ideal"?  Use the Task Scheduler to add it to the Windows start up sequence and you will not have to worry about this issue.  If you use stand by mode, you might have to run ThrottleStop again after you resume.  When properly setup, it is a very efficient program so some users prefer to leave it running, minimized to the system tray.

 

The i5-6500 is a locked CPU.  It can only use the highest multiplier when a single core is active and you also need to have at least the C3 C State enabled in the bios.  If the bios is not setting your CPU up correctly, using ThrottleStop might be helpful to fix that problem too.

[PaulDoyle333]

BD PROCHOT stands for bi-directional processor hot.  This allows other sensors on your motherboard to signal the CPU which forces the CPU to use the minimum multiplier (8).  The CPU behaves exactly the same as if it was thermal throttling but in this case, the CPU temperature is fine.  On some motherboards, it can be either a temperature switch from the voltage regulator or a power consumption switch.  On your motherboard, it is very likely that the Slow Mode switch intended for LN2 users is failing.  The only fix is a new board.  This problem has nothing to do with Windows.  

 

ThrottleStop is the only free software available that lets a user disable the BD PROCHOT signal path.  When you uncheck BD PROCHOT, that blocks signals from the defective switch getting to your CPU.  A simple fix and after you disable BD PROCHOT, you should be able to exit ThrottleStop and the BD PROCHOT signal path will remain disabled.  ThrottleStop also has an option that you can add to the INI configuration file.

 

ExitTime=5

 

This option tells ThrottleStop to exit 5 seconds after it starts.  ThrottleStop will start up, fix the problem and then quietly exit.

 

Why is ThrottleStop "not ideal"?  Use the Task Scheduler to add it to the Windows start up sequence and you will not have to worry about this issue.  If you use stand by mode, you might have to run ThrottleStop again after you resume.  When properly setup, it is a very efficient program so some users prefer to leave it running, minimized to the system tray.

 

The i5-6500 is a locked CPU.  It can only use the highest multiplier when a single core is active and you also need to have at least the C3 C State enabled in the bios.  If the bios is not setting your CPU up correctly, using ThrottleStop might be helpful to fix that problem too.

Thank you very much i'm just glad i know exactly what the problem is as I was hoping it wasn't the CPU . Stupid LN2 Slow-Mode feature on a B150 board lol .System running perfect the last few days with throttlestop . Not ideal but what can you do i could RMA the board but it can be really time consuming .

[PaulDoyle333]

Thank you very much i'm just glad i know exactly what the problem is as I was hoping it wasn't the CPU . Stupid LN2 Slow-Mode feature on a B150 board lol .System running perfect the last few days with throttlestop . Not ideal but what can you do i could RMA the board but it can be really time consuming .

By not ideal I mean the annoying super bright red L.E.D that flickers on and off all day . But once the system is working at its correct speed I can live with it . 

[BuntzenB]

By not ideal I mean the annoying super bright red L.E.D that flickers on and off all day . But once the system is working at its correct speed I can live with it . 

 

that is what black ductape is for

[PaulDoyle333]

that is what black ductape is for

This is true.

[BocuD]

maybe you can try replacing the thermal compound.

[saminjapan]

You might not have enough power from your Power Supply...... If it only plummets under load, it could be because your GPU sucks up the power, and your CPU is left dry.... how many watts is your power supply, and what GPU are u running?

[PaulDoyle333]

You might not have enough power from your Power Supply...... If it only plummets under load, it could be because your GPU sucks up the power, and your CPU is left dry.... how many watts is your power supply, and what GPU are u running?

Nope tested with my brothers PSU , I have no GPU at the min just sold my GTX 770 so system is pulling less than 100 watts from the wall . 

[saminjapan]

Nope tested with my brothers PSU , I have no GPU at the min just sold my GTX 770 so system is pulling less than 100 watts from the wall . 

Check this out: http://hardforum.com/archive/index.php/t-1762299.html

Could be a faulty CPU thermal sensor for the BD PROCHOT thing; it might be dedicated, so while windows might report otherwise, BD PROCHOT could be getting different signals, and cause throttling to occur.... doesn't look like you can reinstall it, or just delete it or anything....

If it is from windows, you can delete it, then run SFC (system file checker) to re-download it.

Only REAL fix looks like the one your currently using....

[stukov]

Hi all

 

This is response from MSI Support regarding the issue, there's no need to use Throttlestop. Just one different setting in UEFI will turn that sensor off.

 

Quote

Thanks for contacting MSI technical support.

Regarding your concern,firstly,please make sure that the Slow 1 switch is setted to Normal mode.Secondly,if the issue persists,kindly please enter bios to set the Intel Adaptive Thermal Monitor to disabled to check again.Please refer to image below for a try.Thanks!

Thanks for your cooperation in advance!

Best Regards,
MSI Technical Support Team

 

Hope that helps

[PaulDoyle333]

On 2/29/2016 at 7:55 PM, stukov said:

Hi all

 

This is response from MSI Support regarding the issue, there's no need to use Throttlestop. Just one different setting in UEFI will turn that sensor off.

 

 

Hope that helps

Thanks dude , the little switch was the first thing I checked . The second option you suggested works a treat tho when I disabled (Intel Adaptive Thermal Monitor) . My CPU no longer reports 0.80ghz in the bios . Cheers man I don't need throttlestop anymore   :-) . The little red light stays on but system running at correct speed now without throttlestop :-) Thank you Thank you Thank you :-)

[Jeff Mas]

@PaulDoyle333 

 

Thank you so much sir! This resolved my problem. I have the same mobo and processor. I bought it February of this year and its been working great until after 3 months of usage. It was so lag on games ive been playing (Tree of Savior, LOL and BnS) My FPS is dropping almost 5FPS and i thought its my Zotac GTX 970. I have tried everything, the newest and oldest Nvidia graphics driver on their website and also Windows 8, 8.1 and 10 and still the same. I was ready to RMA the GPU until i read this and Boom, my PC is back to normal and been working perfectly again. I cant thank you enuf! Kudos!