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Anyone have a 7920X yet?

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Topweasel

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You cant really reduce this by some mathematical formula. I would prefer 7940x or 7960x over 7920x too, but saying its not really better than 7900x is just silly :) no offense

And while i guess you would certainly see a difference between 1-core and 3-core CPU, 10/12 and 16/18 are pretty similar ratios and if anything, you would see slightly bigger difference between 12 and 10, than between 18 and 16 (assuming same clocks).
You are missing the point. When someone says 2 cores more are not noticeable that same thing applies to every level a 10c isn't that much of an upgrade over 8c, 12c over 10, 14 over 12, 16 over 14, and so on. If adding two cores isn't helpful where does it end (like he said Single core).

There are other reasons beside little difference that makes the 7920x a bad chip. One of those is MCC die power usage even though its only 2 cores more than the 7900. That its base and all core clocks are smaller than the 7900 by such a degree it makes the extra 2 cores be not worth it (over all processing power is roughly the same). Another big decider is people typical buying trends. That would be the three major tiers. First is cheapest that fits requirements. Second is value, which chip is the best value of the product line (why back in the day I got a 7950 over a 7970, or today people would get a 1080 over a 1080ti). Third is absolute best. A 7920x doesn't fit any of those catagories. So the only thing it has going for it is possibly being the best a person can afford, which honestly isn't going to be that much, I mean how many people are going to be putting together a 3500-5k system and choose the CPU as the item with a limited price tag and even then how can they look a 7900 and its better clocks and better OC potential, and decide that the 7920x is worth spending more on. the 7920x is the worst CPU in a lineup filled with confusing and oddly positioned CPU's.
 
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Timmah!

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Jul 24, 2010
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You are missing the point. When someone says 2 cores more are not noticeable that same thing applies to every level a 10c isn't that much of an upgrade over 8c, 12c over 10, 14 over 12, 16 over 14, and so on. If adding two cores isn't helpful where does it end (like he said Single core).

There are other reasons beside little difference that makes the 7920x a bad chip. One of those is MCC die power usage even though its only 2 cores more than the 7900. That its base and all core clocks are smaller than the 7900 by such a degree it makes the extra 2 cores be not worth it (over all processing power is roughly the same). Another big decider is people typical buying trends. That would be the three major tiers. First is cheapest that fits requirements. Second is value, which chip is the best value of the product line (why back in the day I got a 7950 over a 7970, or today people would get a 1080 over a 1080ti). Third is absolute best. A 7920x doesn't fit any of those catagories. So the only thing it has going for it is possibly being the best a person can afford, which honestly isn't going to be that much, I mean how many people are going to be putting together a 3500-5k system and choose the CPU as the item with a limited price tag and even then how can they look a 7900 and its better clocks and better OC potential, and decide that the 7920x is worth spending more on. the 7920x is the worst CPU in a lineup filled with confusing and oddly positioned CPU's.
1. Arachnotronic said he would take 7900x over 7920x and then only other alternative would be 7980xe. This makes no sense, because either you care about number of cores, in which case 7980xe is the best possible chip and in extension you have to consider 7920x to be better choice than 7900x. Or you dont care about the core number that much, in which case its totally OK to take 7900x over 7920x, but then again why not apply the same rules to 7960x and 7980xe? You dont mind 2 less cores with 7900x, but you do with 7960x?

I understand the allure of 7980xe, i would buy it myself over any other alternative, if i was willing to pay the money. But there is no way one can rationally justify those choices he said he would make.

2. What MCC power usage? Do we really know its that much higher than LCC, or do we just assume that it has to be cause of more cores? The base clock is completely irrelevant, the all-core turbo-clock is just 200 MHz lower against 7900x (3,8 to 4Ghz). You want to tell me those additional 200Mhz make the extra 2 cores not worth it? Tough to believe.

There is a poster on Overclock.net from Netherlands, who ran his 7920x at 4,6Ghz and 1,2V. Not that far off from 7900x again, is it? Per info from him, it actually looks like MCC chips dont suffer from the TIM issue as much as LCC chips, probably cause of the bigger die area.

Bottom line, 7920x is far from the worst CPU in the line-up. Maybe to you, based on your personal criteria/preferences, which is absolutely fine, but there will be many people who will see it other way.
 

Topweasel

Diamond Member
Oct 19, 2000
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1. Arachnotronic said he would take 7900x over 7920x and then only other alternative would be 7980xe. This makes no sense, because either you care about number of cores, in which case 7980xe is the best possible chip and in extension you have to consider 7920x to be better choice than 7900x. Or you dont care about the core number that much, in which case its totally OK to take 7900x over 7920x, but then again why not apply the same rules to 7960x and 7980xe? You dont mind 2 less cores with 7900x, but you do with 7960x?

I understand the allure of 7980xe, i would buy it myself over any other alternative, if i was willing to pay the money. But there is no way one can rationally justify those choices he said he would make.
I was explaining a post someone else made. Something that comes up in SL-X or TR threads, someone saying in regards to a CPU only a 2 Cores larger that it is only 2 cores and no one would notice the difference. It was a joke that it meant you work your way down to Pentium with that thought process. But it was part of the point, once you get beyond 4 cores you are really working on a different playing field in terms of use case and the reality is chances are at each step there is probably a measurable difference with an extra 2c4t. Otherwise you probably shouldn't be looking at CPU's with high core counts anyways. This portion was actually in support of a CPU like the 7920x. If you are running something that utilize a 7900x, then you are probably running something that would benefit from 2 more cores.

2. What MCC power usage? Do we really know its that much higher than LCC, or do we just assume that it has to be cause of more cores? The base clock is completely irrelevant, the all-core turbo-clock is just 200 MHz lower against 7900x (3,8 to 4Ghz). You want to tell me those additional 200Mhz make the extra 2 cores not worth it? Tough to believe.

There is a poster on Overclock.net from Netherlands, who ran his 7920x at 4,6Ghz and 1,2V. Not that far off from 7900x again, is it? Per info from him, it actually looks like MCC chips dont suffer from the TIM issue as much as LCC chips, probably cause of the bigger die area.

Bottom line, 7920x is far from the worst CPU in the line-up. Maybe to you, based on your personal criteria/preferences, which is absolutely fine, but there will be many people who will see it other way.[/QUOTE]

I have stated before, power usage on Intel or AMD CPU's is pretty linear. The difference is that on the AMD Threadripper side by having 2 dies you can take the power of each configuration as we know from the Ryzen lineup while keeping an eye on clock speed and just double up. This doesn't work as well on SL-X in regards to LCC due to a bit of large die overhead in comparison to lets say a 4c die (7600/7700). There was a measurable difference between 7900 and 7820 but the 7820 was still more power than a doubled up 7700 at the same clock speed. That the 7800 was more than 50% more than a 7700. Meaning that there was a power overhead regarding the die with as many cores as it had whether or not those cores were disabled. This should follow with MCC that the power usage of a 7920x should still be higher than the 7900 then the 7900x is over a 7820. You could be right and the larger die leads to better thermal transfer making it easier to not spike the CPU temp like what people were seeing on LCC but that won't remove the fact that the power usage will still be even more through the roof and that you will have that much more power to have to dissipate at any given clock speed. Most of this is conjecture based on the information on hand we will have to see when it's released.

But I didn't just magically make up the idea that the 7920x isn't going to be considered a great CPU in the lineup. I just parroted reasons others have stated. At stock the 7900 is going to have such a clockspeed advantage that in tasks that utilize the cores well the 7900 will be as strong or maybe even stronger even though it has two more cores. It should have less OC potential. It is more expensive. Other than an extra 2c4t for VM work there would be little that the 7920 would do better than the 7900. Where as a 7940x would have 40% more cores with similar clocks to the 7920 with the same OC potential, same thing with the 7980xe with 80% more cores and the 7960x in between. If you can't afford a 7940x you would be better off with the 7900x.
 

Timmah!

Senior member
Jul 24, 2010
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But I didn't just magically make up the idea that the 7920x isn't going to be considered a great CPU in the lineup. I just parroted reasons others have stated. At stock the 7900 is going to have such a clockspeed advantage that in tasks that utilize the cores well the 7900 will be as strong or maybe even stronger even though it has two more cores. It should have less OC potential. It is more expensive. Other than an extra 2c4t for VM work there would be little that the 7920 would do better than the 7900. Where as a 7940x would have 40% more cores with similar clocks to the 7920 with the same OC potential, same thing with the 7980xe with 80% more cores and the 7960x in between. If you can't afford a 7940x you would be better off with the 7900x.
Regarding 7900x, as i said, clockspeed advantage at stock it has over 7920x is just 200MHz. While Cinebench is not be all end all, 7900x with its clockspeed advantage scores about 2200 points, while 7920x 2500. To get 2500 out of the 7900x, you need to look at the 4,6GHz overclock. Its not so easy to replace 2 additional cores.

I can tie the 5960x score with my 6850k too - if i OC it to 4,2. Thats about 700 MHz more than 5960x at stock in order to make up for 2 additional cores, not meager 200.

Regarding less OC potential than 7900x, to quote the Silicon Lottery´s guy:

"Temperatures are pretty much the same on the 12 core compared to the 10 core, overclocks are about 100MHz lower."


Regarding 7940x, so you assume that its going to have similar clocks to 7920x and same OC potential, but at the same time 7920x will have less OC potential than 7900x? Even though the difference between chips is in both cases 2 cores... any logic behind that?
 
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Topweasel

Diamond Member
Oct 19, 2000
5,060
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Regarding 7900x, as i said, clockspeed advantage at stock it has over 7920x is just 200MHz. While Cinebench is not be all end all, 7900x with its clockspeed advantage scores about 2200 points, while 7920x 2500. To get 2500 out of the 7900x, you need to look at the 4,6GHz overclock. Its not so easy to replace 2 additional cores.

I can tie the 5960x score with my 6850k too - if i OC it to 4,2. Thats about 700 MHz more than 5960x at stock in order to make up for 2 additional cores, not meager 200.

Regarding less OC potential than 7900x, to quote the Silicon Lottery´s guy:

"Temperatures are pretty much the same on the 12 core compared to the 10 core, overclocks are about 100MHz lower."


Regarding 7940x, so you assume that its going to have similar clocks to 7920x and same OC potential, but at the same time 7920x will have less OC potential than 7900x? Even though the difference between chips is in both cases 2 cores... any logic behind that?
Because the 7920x is an 18 core CPU and the 7900x is a 10 core CPU. Luckily we have Anandtech doing a review as we speak, but I am not going to base my opinion just on a single person who's sole job is to find golden samples.

Edit: Scratch that. Apparently the 7920 and 7940 aren't worth covering.
 
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Timmah!

Senior member
Jul 24, 2010
734
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Because the 7920x is an 18 core CPU and the 7900x is a 10 core CPU. Luckily we have Anandtech doing a review as we speak, but I am not going to base my opinion just on a single person who's sole job is to find golden samples.

Edit: Scratch that. Apparently the 7920 and 7940 aren't worth covering.
Yeah, just found out, to my annoyance :-D Was looking forward to 7940x review but tough luck.
 

Topweasel

Diamond Member
Oct 19, 2000
5,060
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When did the 7920X 12 core chip get 6 more cores?
When it was made on the MCC die. I am not talking about active cores but power usage is increased and OC potential in theory would be limited by the die configuration which like 60% larger than 12 cores needs to be.
 

Topweasel

Diamond Member
Oct 19, 2000
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HCC.

We have LCC, HCC and XCC.
Yeah, It's three core sizes. Small, medium, and large. I am not into this whole relabeling lake Grande and Venti. I will always default back to the three globally understood sizes since a kid thanks to the Critic.
 

Topweasel

Diamond Member
Oct 19, 2000
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There is nothing to default back to. The original names are the ones I listed but feel free to argue.
Nothing to argue. You give me a single object in three sizes it's small, medium, and large to me no matter how much a company wants me to call it a Venti.
 

eddman

Senior member
Dec 28, 2010
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Nothing to argue. You give me a single object in three sizes it's small, medium, and large to me no matter how much a company wants me to call it a Venti.
You can call it medium, but not MCC. That's not its name.
 

eddman

Senior member
Dec 28, 2010
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It's a medium core count die to me.
Yes, not "MCC". You are only going to confuse people. I don't get why you even swim against such a thing. It's a chip name. It reminds me of a person who desperately wanted Pascal to be named 1800 but nvidia went with 1080.
 

Topweasel

Diamond Member
Oct 19, 2000
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Yes, not "MCC". You are only going to confuse people. I don't get why you even swim against such a thing. It's a chip name. It reminds me of a person who desperately wanted Pascal to be named 1800 but nvidia went with 1080.
I have been typing MCC since before we had any clear designation from Intel (and honestly even that is pretty lacklustre) it's not something I am going to change any time soon.
 

eddman

Senior member
Dec 28, 2010
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I have been typing MCC since before we had any clear designation from Intel (and honestly even that is pretty lacklustre) it's not something I am going to change any time soon.
Almost EXACTLY the same thing that Pascal 1800 person said.

P.S. I hope it doesn't give the impression that I'm being disrespectful. I just find it odd and see no reason for it.
 

Topweasel

Diamond Member
Oct 19, 2000
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Almost EXACTLY the same thing that Pascal 1800 person said.

P.S. I hope it doesn't give the impression that I'm being disrespectful. I just find it odd and see no reason for it.
I don't know what story was with the Pascal 1800. But keep in mind that it wasn't just a guess. We knew the previous stuff was LCC and HCC, then they upped the core count in the middle, since this is just internal not even code names but just dev team values, it made sense that with a third one the middle one would be medium. I just also don't approve of companies trying to shake up the values for the sake of making it sound like more than it is. So with those two it's hard for me to call the middle die "huge" and the biggest "extreme". Hell when it comes to LCC it just occured to me and probably why MCC is HCC, is that the L stands for Large and if that's the case I am taking a stand.

Proper use of the 3 standard and globally recognized sizes forever!!!
 

eddman

Senior member
Dec 28, 2010
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I don't know what story was with the Pascal 1800. But keep in mind that it wasn't just a guess. We knew the previous stuff was LCC and HCC, then they upped the core count in the middle, since this is just internal not even code names but just dev team values, it made sense that with a third one the middle one would be medium. I just also don't approve of companies trying to shake up the values for the sake of making it sound like more than it is. So with those two it's hard for me to call the middle die "huge" and the biggest "extreme". Hell when it comes to LCC it just occured to me and probably why MCC is HCC, is that the L stands for Large and if that's the case I am taking a stand.

Proper use of the 3 standard and globally recognized sizes forever!!!
The story of this one person with Pascal was that he wanted nvidia to name it 1800 yet they named it 1080. He didn't accept it and kept calling it 1800 for a while. This MCC thing reminds me of that.

So what if they re-purposed the names? It's just going to be confusing if you write HCC instead of XCC and then people think you meant the actual 18 core HCC and then you'd have to explain that you mean the 28 core part, etc. I see no point in not accepting official naming schemes.

I don't know. It's your choice. No problem with that.
 

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