VCore vs LLC

[TimmiB]

Hi there,

after couple of years without an AMD CPU i got a 3800XT now and i am very happy.

The only question is how critical should loadline calibration be considered?

The 3800XT runs at 4600 MHz on all Cores with 1.33125V, which is fine as far as i can tell. But to avoid crashes LLC of the highest Level is needed. (ASRock calls this Level 1).
All other Voltages are set to Auto. RAM @ 1.35V.

Temperatures are great. CPU far below 75°C.

Any concerns?

Regards

Tim

 

[freeagent]

Sounds really good!

Running level 4 on an Asus myself.. 5 being the highest. Very jelly sitting here looking at your numbers!

 

[bigtallanddopey]

4.6Ghz on all cores is pretty good, have you stress tested it fully at that speed? If so, seems a very good chip.

As for LLC, yeh that’s normal, especially when you are overclocking as high as you have. I would be careful though as when you pick the highest level of LLC it can overvolt when the system is idling. This is all needed because of Vdroop or voltage droop. Basically when you are overclocking to high levels there can be a discrepancy between the voltage required and the voltage supplied. LLC tries to make up for this discrepancy. High levels of LLC can sometimes cause an overshoot when running at fully load and like I said they can cause too much voltage compared to what is required when at idle.

For day to day use it is often better to have a mid level LLC, however you probably won’t be able to hit 4.6Ghz. That’s why with ryzen, especially the 3000 & 5000 series it if often better to leave them at stock and let the boost technology take care of things. You can often get better performance at stock.

I’m not a massive expert on LLC. Sure someone can explain it more if needed.

 

[TimmiB]

4.6Ghz on all cores is pretty good, have you stress tested it fully at that speed?

Not yet, just normal operation/gaming till now. Is it correct that the Cinebench R23 is the endboss due to AVX?

So there is daily use stable, a Prime95 stable and a Cinebench R23 stable?

 

[TimmiB]

I just tried - even at 1.4V Cinebench is crashing. For Prime95 i have to raise the VCore to 1.4V to avoid immediate crash.

- - - Auto-Merged Double Post - - -

At 4500MHz and 1.4V VCore. Cinebench is not crashing in the first run.

Personally i don't see any benefit from running hours of stressstests. Since in normal use, everyhing is fine. Maybe when i start working with blender again, i might consider step down the clocks again.

The high temperatures for that time and high current, which do not come for free by the way, is something i am not willing to take.

 

[bigtallanddopey]

Not yet, just normal operation/gaming till now. Is it correct that the Cinebench R23 is the endboss due to AVX?

So there is daily use stable, a Prime95 stable and a Cinebench R23 stable?

You can usually get through cinebench as it is so short, I tend to use cinebench to check stability after an oc change. Prime95 is usually the one I use to test if things are fully stable, run it for 20 minutes is often enough.

To be honest, if it is stable gaming then sometimes you can get away with leaving it at that if you are happy. You just may get the odd crash if something suddenly taxes the cpu.

 

[TimmiB]

That was the kind of answer i was hoping for.

 

[freeagent]

I've seen prime fail after 24 hours.. I've also had games crash on a prime stable system, so to me its a waste of time.

Edit:

Try Linpack Xtreme 1.15