Should I disable the second CCD on my 7900X?

[jarablue]

I have a 7900X with two CCDs that have 6 cores each. Should I disable the second CCD and just use 6 cores? This is for gaming performance only.

Or should I keep both CCDs on and use the 12 cores and cross CCD latency?

I have the option in my bios to do this. Just came out.

 

[eidairaman1]

I have a 7900X with two CCDs that have 6 cores each. Should I disable the second CCD and just use 6 cores? This is for gaming performance only.

Or should I keep both CCDs on and use the 12 cores and cross CCD latency?

I have the option in my bios to do this. Just came out.

Do some testing with it on and then off and see if it justifies being turned off

 

[Kapone33]

Before you do that. Ask yourself how fast a nano second is and realize how much of a nothing burger what you worry about is. If you really want to know take City Skylines 2. That is probably one of the most intensive CPU Games there is. I have seen as much as 60% CPU usage in that Game. That means that it is using both CCDs on my 7900X3D. I even had one of the people that love to bash AMD tell me it is not latency but topology. Was the 5900X slow in Gaming? No not really. Is a 7900X faster than a 5900X in Gaming? Read the reviews and yes it is. 5.7 Ghz is nothing to sneeze at. Doing it at under 150 watts is exemplary. You have one of the fastest CPUs ever made just enjoy it as it was designed. Do you really believe the Community knows more than AMD's engineers?

 

[lexluthermiester]

I have a 7900X with two CCDs that have 6 cores each. Should I disable the second CCD and just use 6 cores? This is for gaming performance only.

Or should I keep both CCDs on and use the 12 cores and cross CCD latency?

I have the option in my bios to do this. Just came out.

No, not worth it. Leave well enough alone. No change of that nature is going to render a result that will justify the fact that your cutting your CPU in half.

Do you really believe the Community knows more than AMD's engineers?

To be fair, that has happened.

 

[Dr. Dro]

No. If you have run into a corner case, use process lasso tool to isolate the affected game into one specific CCD. Such issues are rare and affect all Ryzen 9's, similarly to how some very specific games still misbehave with Intel E-cores. The 7900X should behave similarly to the 5900X and isn't affected by the bad topology problems of the 7900X3D.

 

[Hyderz]

You purchased all 12 cores, use all of it

 

[natr0n]

I have a 5950x when I disable 1 ccd the better core hangs around 5GHz on every core.

So in your case higher clocks on new platform try it out.

Even have a 5600x and it can play anything with only 6 cores with smt off

Honestly games dont need so many cores. You save power and get higher clocks when you cut back on cores.

 

[Bill_Bright]

To be fair, that has happened.

True, but also to be fair, the default settings AMD, as well as Intel, NVIDIA, Microsoft, ASUS, Gigabyte, MSI, Crucial and [fill-in-the-blank] set do work best for the vast majority of users. With 100s and 100s of millions of Windows computers out there, no company can test with, or even anticipate every possible scenario. So there will always be a few "exceptions". But those "exceptions" members of the community report are just that, "exceptions". And exceptions are not the norm, nor do they make the rule.

Point? Set biases aside and don't assume the engineers, designers and developers are wrong. And to that point,

Should I disable...

Or should I keep... .

Do some testing with it on and then off...

...then tell us what you learned.

I agree with eidairaman1 - try it and see what happens then report back to us and tell us what worked best with YOUR setup. And speaking of "your" setup, fill out your TPU System Specs so we know what "your" setup is.

 

[freeagent]

My 5900X games just fine

 

[Frick]

I have a 7900X with two CCDs that have 6 cores each. Should I disable the second CCD and just use 6 cores? This is for gaming performance only.

Or should I keep both CCDs on and use the 12 cores and cross CCD latency?

I have the option in my bios to do this. Just came out.

Sell it and buy a 7800x3d, or a 9800x3d when that comes out. If you're exclusively using it for gaming I mean, and if it's important.

 

[lexluthermiester]

True, but also to be fair, the default settings AMD, as well as Intel, NVIDIA, Microsoft, ASUS, Gigabyte, MSI, Crucial and [fill-in-the-blank] set do work best for the vast majority of users.

Not always and not recently. All the nonsense with Intel's CPUs recently are evidence of that and the same kind of thing(though with less disastrous effects) with Ryzens a few years ago.

A lot of the time, defaults are best, but not always.

And speaking of "your" setup, fill out your TPU System Specs so we know what "your" setup is.

That is not an obligation. We can not assume that what someone has in there "specs" is going to be what they're discussing, because it frequently isn't.

@jarablue
Windows is smart enough now to know what the fastest cores are in a given CPU package and will shift heavy workloads to them while keeping itself on the slower cores. You start disabling any of them and you will hurt your performance because you might be disabling your best cores and will be forcing Windows itself to operate on cores that it would otherwise be allocated completely to your games.

Leave your system as it is. You will gain nothing from disabling one CCX or the other.

 

[arbiter]

Maybe limiting games to 1 CCX might yield what you are wanting performance wise using a program like processor lasso without disabling the other.

 

[Kapone33]

No. If you have run into a corner case, use process lasso tool to isolate the affected game into one specific CCD. Such issues are rare and affect all Ryzen 9's, similarly to how some very specific games still misbehave with Intel E-cores. The 7900X should behave similarly to the 5900X and isn't affected by the bad topology problems of the 7900X3D.

Are you ever going to stop? Answer this question. Is a 7900X faster in Gaming than a 7900X3D? Be honest.

 

[lexluthermiester]

Is a 7900X faster in Gaming than a 7900X3D? Be honest.

Depends on the game. Generally no, but not always.

 

[Bill_Bright]

Not always and not recently. All the nonsense with Intel's CPU recently are evidence of that and the same kind of thing(though with less disastrous effects) with Ryzens a few years ago.

A lot of the time, defaults are best, but not always.

This is distorting the facts. What I said was, for the majority of people, leaving the defaults as is is best. Even with your examples, which did affect more than just a few users, for the majority of users the defaults remained the best for them. You are implying everyone who had those CPUs needed to change the defaults. That was not true.

And FTR, my comment does not preclude those manufacturers from pushing out a firmware update that changes the defaults.

That is not an obligation. We can not assume that what someone has in there "specs" is going to be what they're discussing, because it frequently isn't.

Okay, fine Lex.

Yes, to be nitpicky, you are right. I for one, have 5 computers here so your point is valid.

MY POINT was, has been, and still is, if OPs wants to ensure applicable advice, they need to tell us their system specs. Filling out the TPU specs is easy, and can be done once (until there are HW changes). Then the OP can just refer to them, or state the specs if a different machine.

Your comment got us no where closer to knowing what HW @jarablue is working with.

 

[eidairaman1]

He hasn't been back so lets wait

 

[wheresmycar]

With the 7900X3D turning off CCD1 can benefit some CPU-bound games, as it forces the system to use CCD0 with the 3D Cache which improves cache dependent performance. The same doesn’t apply to the standard 7900X, where both CCDs are basically identical in design with only minor inter-CCD comms latency differences which will hardly go noticed in real-time gameplay.

Personally I would still test both settings. I'm just naturally curious, a curious cat, a cat that likes to poke the CPU just to see if anything exciting happens.

 

[Dr. Dro]

Are you ever going to stop? Answer this question. Is a 7900X faster in Gaming than a 7900X3D? Be honest.

No, I will not. And I have repeatedly told you, I don't care about your feelings. My only compromise is with the truth, not allegiance with a corporation or making up stories to make myself feel better about my purchasing decisions.

With the 7900X3D turning off CCD1 can benefit some CPU-bound games, as it forces the system to use CCD0 with the 3D Cache which improves cache dependent performance. The same doesn’t apply to the standard 7900X, where both CCDs are basically identical in design with only minor inter-CCD comms latency differences which will hardly go noticed in real-time gameplay.

Personally I would still test both settings. I'm just naturally curious, a curious cat, a cat that likes to poke the CPU just to see if anything exciting happens.

Exactly. Even then, disabling CCD1 entirely should not be necessary on the 7900X. The Zen 5 X3D's will have 2 3D dies so you won't need to disable anything on them, either. They'll behave just like the normal R9's.

 

[Macro Device]

Sorry but this thread smells like "Guys, I bought a Lambo but I got a bit too much throttle on our tarmac. Should I cut my engine in half so I drive smoother?"

You can disable one of CCDs just for lulz and testing purposes but this won't amount to any significant improvements. Leave all cores enabled as far as they're not damaged. Tune your RAM, cache speed and whatnot if you feel FPS starved but don't disable the cores.

 

[gffermari]

If you care about the last fps and have a 4080 or better, sell the 7900X and buy a 7800X3D or 9800X3D.
In any other situation, you shouldn't care since you are GPU limited.

 

[Bill_Bright]

My only compromise is with the truth

Huh? Freudian slip or cranial flatulence?

"The truth" - at least in technical discussions - is the one area where you should NOT compromise.

***

Instead of talking about CPUs the OP does NOT have, I suggest we wait until he comes back with an update.

 

[Dr. Dro]

Huh? Freudian slip or cranial flatulence?

"The truth" - at least in technical discussions - is the one area where you should NOT compromise.

***

Instead of talking about CPUs the OP does NOT have, I suggest we wait until he comes back with an update.

Bill, this is an off topic remark. It's more bout this feud kapone has with me because he's fanatical about AMD and I am bitterly indifferent towards them - and as such willing to call them out on BS he more than happily gives a pass. Compromise perhaps might have been the wrong word - it's "committal" that I meant.

Apologies for the misunderstanding

 

[jarablue]

I'm just going to keep the 12 cores enabled. Thanks. I don't care about an extra 5fps if that.

I'm good. Carry on.

 

[Dr. Dro]

I'm just going to keep the 12 cores enabled. Thanks. I don't care about an extra 5fps if that.

I'm good. Carry on.

Realistically speaking: not even a single fps to be gained in your case. Only lose it - since you'd be effectively turning your chip into a 7600X.

 

[lexluthermiester]

This is distorting the facts.

Not at all. I was highlighting facts, well known as it were, not distorting them.

I'm just going to keep the 12 cores enabled. Thanks. I don't care about an extra 5fps if that.

I'm good. Carry on.

Cool beans! Cheers eh?