NB frequency changing constantly with performance drop

[emdea22]

Greetings everybody, i've recently noticed my northbridge freq keeps changing and i'm loosing fps because of it, now i figured this is the perfect opportunity to create an account here as i've been to lazy to do it in the past. I will try to post as close to the guidelines as possible.

 

Problem: NB freq ranges from 1300 to 1600(default) no matter what i set it at. If i set it at 2000 it will range from 1300 to 2000.

 

Specs:

MB: MSI FM2-A55M-E33 

CPU: A6-5400K APU @4.2ghz + 1013mhz GPU

RAM: kingston 1333 cl9 SS @ 2133 cl11 1.5v STABLE

HDD: WD caviar blue single plater 1tb 10EZEX

PSU: shitty 450w probably 200w max - i will get a better one soon

OS: Win7 32bit

 

Now i know this is low end everything but i paid the equivalent of $200 for all the components. Everything is new except PSU, case and ram.

My main rig is mining hard so i needed something to play Dota 2 on. It works flawlessly but i have some frame drops that are related to the drop in NB frequency.

 

This occurs with or without overclocking!

[Hoppa]

Have you checked temps for the north bridge?

Maybe there's a limit set so when it hits that temp it clocks down.

I'm not sure but the north bridge clock speed shouldn't effect the fps too much.

Replacing thermal paste on the chipset heatsinks could lower temps by 10 degrees because some manufactures use pretty crappy stuff.

I'm assuming you've noticed that when it hits 1300mhz that the fps drops.(not any other speed?)

So my guess is to overclock the CPU using the base clock and hopefully it raises the lowest speed (1300mhz) to something higher.

This is complete guess work BTW.

[emdea22]

Thanks for the reply. 

 

No, only NB freq changes, everything else stays at expected values +/- 0.001%

I can only raise the base clock by 5 because this is not an overclocking board plus its an unlocked CPU.

 

I'm mostly looking for an explanation or if there isn't one, which component should i RMA cpu or mobo?

[ig33ku]

What is the temp of the CPU?

[emdea22]

Impossible to tell for sure. These APU sensors are fubar. HWmonitor reports 110C full load, same as hwinfo. MSI utility reports 60C at full load while the heatsink is only warm to the touch. I don't have any better method of measuring temps so i'm guessing MSI utility is closer to reality. I'm mostly worried about the A55 chipset because it burns my finger when i touch it. 

 

Got a reply from msi:

 

"Thanks for contacting MSI technical support.

Regarding your concern,the NB frequency will change with the loading of the system, it is normal. Thanks!

Thanks for your cooperation in advance!

Best Regards,

MSI Technical Support Team"

 

Since when is this normal???Its like saying the cpu should run at half speed

[ig33ku]

Well there usually two sensor for cpus, the one under the heatspreader and the one in the socket under the cpu. I ask because from what you are describing it feels like heat throttling by the cpu. Do you have a small stand fan of some sort? If you do blast it directly at the cpu and run your games and see if the fps improve. Other if someone has a ir temp gun you can borrow hit the base of the heatsink with beam and the back of the mobo where the socket is (remove side case cover) to see how temps are averaging.

[emdea22]

This happens at idle too. Where heat shouldn't be an issue.

[ig33ku]

Ok just out of curiosity can you set the ram back to default speed and voltage? 

[emdea22]

Yes. RAM at default still the same problem. I even updated the bios to the latest version,

[ig33ku]

So that leaves the APU being o/ced that is the issue. Let's try less is more, drop it down 200mhz.

[emdea22]

I have the same problem with ALL settings at default values, including CPU. To be clear even if i DOWNCLOCK the NB to say 1100 it still jumps to 1400-1300. It seems to be fixated at that value sometimes.

[ig33ku]

Well leaves the next obvious cause: the psu. When you get a new one let us know how it goes BTW is it one of those PSU that you plug ur monitor into instead of a separate power outlet?

[emdea22]

No, its a noname from 2009 i think but it was barely used. i tested one just like it with a multimeter and the voltages fall very low under load. It does have SCP and overload protection tested and working at least.

[ig33ku]

You need more juice for the pc to stay fresh. Punageddon!!!

[emdea22]

Got a new PSU - ZALMAN 500LX and the problem persists. I have to say i've been building PCs for a long time now and i haven't had a problem like this before.

 

Since i first started the thread more people have posted about this problem and seems to be related to MSI motherboards. As i contacted MSI they said it was "normal" and would not accept a RMA. Nice support from MSI ... anyway, a guy fixed it by overclocking the memory to 2400 mhz unfortunately i can only go to 2133 so that doesn't work for me. This isn't psu related as i tested the system with 3 PSUs now - one of them a seasonic - 

 

At this point i've tried all the settings i could think of and nothing seems to work. NB is stable as long as i dont use the IGP, as soon as i open chrome or any 3d application the fluctuations start.