amd fx 8350 throttling multiplier x20-x7

[jimbobmcallister]

I have a stable overclock at 4.5mhz
when I move up to 4.6mhx cpu the cpu throttles after prime 95 15mins from x20 to x7 (4600 - 1614 MHz) the cores don't fail - im sure all power saving is disabled - have a solid psu and sufficient cooling for cpu - any ideas please would be great - frustrating have tried many different setting - no luck

 

[Brunostako]

Have you already increased the voltage?

 

[jimbobmcallister]

Yes CPU 1.45, CPU/NB 1.275 - have tried higher (1.475 & 1.325) but doesn't help still doesn't crash any cores but the core are all throttling

CPU LLC Ultra High
CPU/NB High
CPU current - 130%
CPU/NB - 130 %
CPU Power phase control 130 %
CPU Power Duty Control - Extreme

Ram at default timings 1504 9-9-9-28 although my ram is rated 2133 9-11-10-28
have tried CPU bus and multiplier overclocks separately

 

[jimbobmcallister]

is it the vrm temps?

Mobo : M5A99X evo Rev1
PSU : Corsiar hx-750w

 

[NightAntilli]

Are you cooling the backplate? Generally that becomes a temperature wall before the CPU itself.

 

[jimbobmcallister]

thanks for your response - I have never heard of that before - do you mean the back of the mobo behind the cpu - how could I cool that - small fan ?

 

[NightAntilli]

I used the stock fan that came with the CPU, and simply used wires to magically let it hang back there. It stopped my throttling when overclocking my FX-8320. You can also point it directly towards the VRM heat sink, although that was harder for me to do than the back plate, so I chose to install the fan behind the motherboard.

 

[jimbobmcallister]

I just removed rear case cover (front is also off) - still throttling
I have a push pull cpu cooling (2 fans)
with 3 additional fans in the case ( 2 in top - 1 intake over ram & 1 exhaust above cpu/vrm)
also 1 exhaust at rear of case (6 fans plus 1 in the front) is it a temp issue?

is there a way to disable this throttling - all power saving is disabled in bios -

 

[jimbobmcallister]

"I used the stock fan that came with the CPU, and simply used wires to magically let it hang back there. It stopped my throttling when overclocking my FX-8320. You can also point it directly towards the VRM heat sink, although that was harder for me to do than the back plate, so I chose to install the fan behind the motherboard. "

ok thanks that sounds like a good idea - worth trying - appreciate that NightAntilli

 

[jimbobmcallister]

"I used the stock fan that came with the CPU, and simply used wires to magically let it hang back there. It stopped my throttling when overclocking my FX-8320. You can also point it directly towards the VRM heat sink, although that was harder for me to do than the back plate, so I chose to install the fan behind the motherboard. "

your a legend - looks like its working - hung small cpu fan (stock from old amd dual core) just next to cpu on the backplate

as I hung it closer to the vrm area the fan went crazy - didn't know they had sensors in the actual fan thought it was only through the mobo

had this problem for a year now and never thought to post

really appreciate that NightAntilli - good knowledge

all looks good temps stable and multiplier stuck at x20

ill test a little more tomorrow then mark as solution - cheers

 

[NightAntilli]

You're welcome. It's not a fancy solution, and that fan can be pretty loud, but at least you know where the problem is.

 

[jimbobmcallister]

Indeed - tbh the fan is hardly audible to keep it under control - only loud if I actually push it on to the rear of the mobo - but just sitting there is a good solution - only problem is I cant close the back of the case

 

[NightAntilli]

It still works ok with the case closed. I have just enough room to close it since I have quite some room in the back. But not all cases have enough space in the back... You can also try to cool the heat sink of the VRMs next to the processor, by letting a fan blow directly on the sink. I have no experience with this though, but I think it will work.

 

[jimbobmcallister]

how can I share a photo of this in case It can help someone else - cant seem to copy and paste into the thread

 

[jimbobmcallister]

thanks I think I might be able to close the case - but it'll be a close fit

 

[jimbobmcallister]

cooling the vrm heatsink is a much more difficult fix as its tight in there and will have other components to contest with

ill stick with your solution - works great

 

[NightAntilli]

how can I share a photo of this in case It can help someone else - cant seem to copy and paste into the thread

You have to upload it somewhere else like dropbox, and then link it to here with IMG tags.