I found a guide to replace Avx offset with power limit throttling

[Adelin]

https://www.reddit.com/r/overclocking/comments/a7ef1q/using_power_limits_for_avx_stability_on/

Hello,

i was reading this reddit topic, as my 4670k cpu, doesn't support avx offset.

forcing manual voltage, as avx 2 may require more power, is ok but not ideal some people have crash if avx 2 voltage is too low.

I was actually using adaptative mode to get 4.2ghz oc @ 1.225 v and AVX 2 voltage was all over the place.

Using power limit of 62 for long duration and short duration, helped me to throttle cpu speed with avx 2 load, so voltage is not going over 1.3xx volt but 1, 228v with short pike to 1.268v.

with 4.1ghz at 1.175v i had to limit power limit to 60 if i recall well.

Off course i had to guess the perfect power limit to set, as -1 step may throttle turbo speed on non avx task, and +1 avx 2 voltage would raise again.

I find this solution very good for cpu not having avx offset like haswell, broadwell ...
I tryed 4.3 ghz oc ( i had to put 1.275 v to play some games for an hour before crashing,

And avx 2 voltage was over 9000 ! i don't recall it but it was close to 1.35 v

I dunno if i will try to oc the 4670k to 4.3ghz trying 1.280v or even 1.300v if needed, using the power limit guide from reddit.

Grand macho rt work fine without fan connected ( i tryed this way) temperature was around 72°c - 75°c when i tryed avx 2 + power limit.

I guess the heatsink can handle 1.3v .


I'm happy i won't try 1.3v without power limit , as cpu voltage would sky rocket.

I use currently 20Gb of ram 2x 8gb kit 2400mhz gskill 2x2 gb xms 3 corsair 1600mhz.

20 Gb of ram help to mitigate rare case where pagefile was increasing a lot using certain programs.

and 2400mhz speed on 2x8gb kit, would help, only if i had a better gpu than rx 570, in certain cpu limited situations.

At the moment I prefer to use 20 gb of ddr3 at 1600mhz or even 1333mhz, and try to puch cpu to 4.3ghz ( lowering cache ratio to 33 instead of 38, will maybe help with stability at 4.3ghz)


Anyway, i'm pretty happy to have stable 4.2ghz from months @ 1.225v, and 2400mhz / 1600 mhz ram if using 20 Gb kit ( dual channel enabled with both kit )

Power limit, is a thing i never tryed it's so good :)

PS Thermal throttling is another solution: lower frequency paste 80°c, but z87-plus has not this option, only thermal shutdown at 130°c and this can't be lowered, only raising it up to 150°c that is sad, has i would set it at 110 °c

[tacoshy]

if you set a fixed voltage of 1.3V the voltage cant skyrocket as it will always stay at exact 1.3V. Powerlimit is not necessary, beside the fact that the CPu is fine to 1.52V. The maximum voltage you can sue however as always soley depend on your cooling solution.

For Intel teh CAS timigns are more important. 2400MHz for such high cas timigns does not make it worth it over 1600MHz with super low cas timings.

If you do serios OC's you dont pwoer limit you use a fixed voltage as it also highly icnreases the lifespan of the CPu as it causes less microfactures as an adaptive voltage.

[Bad 💀 Motha]

Yea back when I had ddr3 systems, Corsair Vengeance 1600 CAS7 were extremely good compared to others, such as more expensive 2400mhz ram

[Adelin]

Hello Bad and tacoshy, interesting about manual voltage and and cpu life span.

I have set manual voltage while keeping 4.2ghz @ 1.225v.
I hope if an avx 2 instruction set is triggered, nothing will crash.

About power limit Auto from z87-plus set power limit to unllimited.
I hope nothing is wrong here.

Anyway thanks :)

[Adelin]

Hello again,

I am testing rx570 pulse gpu on pci express 3.0 @ x8 wired, so far it works well.

I found if i put cpu fan @ 100%, the gpu been not close to grand macho rt cooler:
Cpu fan is reaching now: 1300rpm up to 1305 rpm.
Before it was 1268 rpm up to 1276 rpm

Off course having p400s x2 front fans runing at medium speed instead of low, help cpu fan motor to attain 1300 rated fan speed.
So a gpu backplate, not touching the cpu heatsink, may block some air flow ,
I never thought about it lol
I have good câble management with p400s, decent enough temperature for a silenced case <<with bad airflow>>

Another find about Z87plus :

Uncore by default is set to auto when you reset bios setting.
Uncore min speed on auto, never lowered ratio.


This is the first time i see uncore working,,.
by setting it @ x/8. instead of auto.
Idle stock temperature droped a bit
cpu fan test @ 100% 26°c on idle for room temp 22.30 °c
For this test everything was on auto minus uncore min @ x8

I never had a temperature that low for cpu when testing fan @ 100%
Temperature increased back, when i switched to auto uncore.
Now i'm back to manual voltage, and auto uncore.
But this test changed my mind :)

[Adelin]

Another finding:

Gpu close to cpu heatsink, is maybe not that much as a problem, as cpu fan may draw heat from top of backplate, to the case air exit.


I thought gpu at lower part of the case would help because gpu would obtain cold air from the ground, but it's maybe not the case, as case metal where psu sit at ground level ( separated by a mesh metal part i'm talking about, this mesh part is pretty hot.

It's a bit strange, as the gpu fans blow all the hot air outside the case.
I think problem is there is maybe not enouigh clearance between the down side of the case, and gpu fans, to get enough cold air, as cold air was warmed by the gpu been et too low ?

Ok nevermind i dunno how to explain, i think i will try again to check gpu temperature + fan speed when gpu is on top.

ok too much blabla again lol

[Adelin]

Hello,

Note to myself xd

As i can't put a rear fan to the p400s with a grand macho rt,
i tryed to turn the heatsink, i would have been able to put a fan, but the motherboard powering câble, block the path to fan, and ram is covered up.

Interesting thing about not having a rear exhaust fan inside the case, is you can't follow guides, but must try by yourself.

So far the rx570 put at the first bottom pci express slot instead of top pciex, with two fans front tested at different position ( two down, two up one up one down and play a game for 15 min or more, i got results like this:

Temperature in Starlink game reached 83 °c @ 2200 rpm in each fan setup try.

Moving the gpu to First pciexpress 3.0 x16 wired slot, putting two front fans up front position cooling both gpu and cpu

I got after 30 minute of gameplay: 1760 rpm fan 70°c

Off course i uninstalled latest amd driver each time, just in case.
Watt draw from amd overlay around 140 w.

I have three hard drives: 2 hidden inside the rear part of the case, and one close to front fans.

The hard drive tested at different bay slots, putting it at bottom down side, won't block airflow.

Airflow managing , is really difficult.


Not having a rear exhaust fan, you must find a way by yourself to optimized your fan and gpu setup, as guides, forums, won't help you.

There was a hardware forum, where a user did lots and lots of try.
He ttryed things like putting a fan at rear of the case at pciexpress emplacement,

It didn't help cooling the gpu if i remember?
As it would intteract with the gpu fans trying to pulling air from the case.

[tacoshy]

well AIrflow can be hard but also simple and depend a lot on the fens, fan curves and the case you use.

However aslogn as your temepratures are within limits you shouldnt be concerned about temepratures. The hardware is designed to handle a lot of heat. They dont break down just because it gets hot and have enough safety measurements to ensure their own survival.

[Bad 💀 Motha]

That's why I buy Cases based around overall space and possibilities for overall airflow and case fan placements.

[Adelin]

Thanks tacoshy Bad Motha.

So no worry from temp point of view.

Interesting thing i never figure to check before:

if you remove the mesh pannel covering motherboard space to hdd cage.
There is a space separating hdd bay , to let you one 120 or 140mm fan from there

Now if i'm going back to this thread:

It's not explained by review, motherboard manuals, or case manuals, but there is an use for pci express and io motherboard metal shield, been not aligned to the back of the case.
If some cases are not flat, it's for one thing:
Putting fans where flat cases would fail, like a p400s having not enough clearance with hudge heatsinks.

If you check cases from later years, you would see the design change to have a more aesthetic clean look.
Again, noone on the internet, from the time i read review, explained the usage of offseting a motherboards, from pci express and io shield at rear of the case.
It was too late when i figured it.

I bought hte p400s to have enough space to put the case under my desk, but it does disallow use of usb and audio top ports.

ANd off course a meshify case, from one brand, had not enough hdd emplacement.

My realtek alc 892 chip oiutput at rear of the case, deliver huge static noise, and only way to have clean sound, is using output from the motherboards pins, to top of the case.

If i knew i had to put this case on the ground, i would have bought a bigger case and make a giant mistake:

My mother board design , need an offset case design, to have a grand macho rt + rear exhaust fan on.
So at the end, i'm happy of p400s, that does a good job at reducing hdd and fans noise :)
And cable management was great.

[Adelin]

To confirm my find, i checked why meshify c from Fractal, has the space to put an exhaust fan, and i got pictures from the back of the case, where you clearly see the offset, and pci express extensions, are tied insight the case, not outside.

So i'm happy of my investigations.

Wow i must ba a little autistic, i may have to do a test one day just in case lol


You can have almost good flat design witrh a an enthoo pro, so maybe if the phanteks p400s has not this design, is it required a bit more lenght.

P600S also has offset.

[Adelin]

Edit, something better 4.5 GHZ @ 1.390 V, as 1.380v was not enough, cpuz was glitching ( computer freezing for one second.

I thought from the beginning i had a bad cpu not been able to oc, but it does work, even if it does require more voltage than for other 4670k.

78°c i dunno if a 4670k is safe 24:24 with those temps, as if i wait 20 minute pore, i'm sure temp would reach 85 °c easily

Cinebench vary from 1597 @ 4.5ghz up to 1660.
Jump from 4.4ghz to 4.5ghz is not that awesome.



Hello, finally i never thought i would be able to have 4670k oc @ 4.4ghz,

Voltage is 1.332v maybe for 24/24h stable it would need some tweack ( 0.1 up to 0.10 if unlocky voltage, but at last i'm runing cinebench and results r20 version:

1597 cpu best score 163x if i remember
401 one core
3.98x mp ratio

Cpu z max result:

1930
and 482 single score.

i'm happy to have push the 4670k to almost it's limit.
To be stable, i found i had to put 0.50 v per 100Mhz upgrade.
If trying 0.40v per 100Mhz, system would not be stable.

I'm ashamed by almost every mobile cpu doing better than this poor 4670k.

I really want a ryzen 3xxx cpu or 9900k for free lol ( joking)

[tacoshy]

mobile CPU's do betetr as those benchmarks pretty much care for core count and most mobile CPU's are octacores. Outside of a CPU core depending benchmark they wont even perform close to thsoe CPU's.

[Adelin]

Octacore ? wow they went this far with mobile cpu ?

I only remember of expensive i7 quadcore + hyper threading, and i5 dual core + hyperthreading.

That may explain lot of things.

9GHZ on one core is it equal to two cores set @ 4.5 GHZ ?
By the way, i launched occt small data set no avx, 88 °c, and avx 2 101°c ( manual voltage)

I will check 4.4ghz temperature, and if not good, 4.3ghz.

I tryed creed odyssey @ 4.2ghz in an area i got only 32 fps with cpu @ 100%.
@ 4.5GhZ the same temple, 42 fps 2560x1440 with highest settings minus fog, aa, and another setting dropped.

I'm still hugely gpu limited, but wow this game eat my overclock :) and still 98¨cpu usage in same area up to 100%
It's + 0,050 per 100 mhz increase not 0,50 xd