Old PC died - Building new one

[dgianstefani]

Correct, there really aren't. Most software has no issue with this very specific problem and even where there is some performance to be lost it's insignificant.

What is a latency-sensitive application?

A latency-sensitive application can be any application where high or variable latency is going to negatively affect the application performance.

www.redhat.com

Here's some knowledge to help you out.

 

[Vya Domus]

Here's some knowledge

No bro, you're in need for far more knowledge than me here.

Those kinds of operating systems are made more for embedded uses cases not your average consumer desktop use by the way, that's why latency matters more. Controlling I/O devices in car, latency is important, playing fortnite and compiling code, not so much. And if you really are concerned about latency in those applications you're not even going to use a regular of the shelf system because they suck no matter what, those things run on SoCs, microcontrollers, etc.

 

[Princess Garnet]

A 33.3% higher tolerance for high core count usage before hitting the latency penalty is pretty significant, big perk of the 7950X. Besides, like you said, a 7900X is faster than a 7700X when you use more cores for productivity, it's just the downsides of the six core design are more apparent than those of the eight core design even in multi CCD chips in any real time task like gaming or audio work, for example.

I agree with those points. I just didn't see the point in suggesting there's something wrong with a 7900 in particular.

If you have a use case for it, it's fine. The 7800X3D (or just from a cost perspective alone, even the 7700X) are better choices if you don't need the extra cores of course, but none of those drawbacks you mention really matter enough if you do have a use-case for the extra cores, since the performance the extra cores brings will far, far outweigh them. Of course the 7950 is better... but that goes without saying as it's also more expensive. The 7900 is fine, just perhaps a bit niche.

 

[Vya Domus]

I just didn't see the point in suggesting there's something wrong with a 7900 in particular.

Of course there isn't. He always barges in with these bizarre claims.

 

[dgianstefani]

I agree with those points. I just didn't see the point in suggesting there's something wrong with a 7900 in particular.

The only point I made was that the 7900 is just a six core, with another six core bolted on (but accessing those extra cores comes with a cost). For all intents and purposes it behaves as a six core to applications. If you use more than those six cores you have signifcant inherent downsides that may or may not impact your work depending on if it's real time or not. The argument I'm making is to either go for the actual 7950X, an Intel chip, or stick with a chip that behaves like a monolithic one. Many people who aren't enthusiasts do not know about or understand these pitfalls of multi CCD chips, since they're a relatively new concept.

Seems that rubs certain people who bought one of those six core pro duo super duper glued editions up the wrong way.

AMD fanboys like to rip on Intel for their non-homogenous architecture with E cores, but it's a very similar story in a different metric when you compare multi CCD chip behaviour to single CCD behaviour. Except the Windows scheduler has a harder issue with the latency problem considering there is no hardware thread director on AMD chips to make up for it. Hence why using Process Lasso can prove extremely beneficial to some applications/games.

 

[gurusmi]

Do you know of any cooler that doesn't fit and uses the AM4 stock backplate ?

The AM4 coolers don't fit at the AM5 socket. No matter if an original or individual backplate.

The only point I made was that the 7900 is just a six core, with another six core bolted on

Not neccessarily. It could also be a full 8 core on the 1st ccd with 4 cores on the second CCD. 6+6 = 8+4

 

[dgianstefani]

Not neccessarily. It could also be a full 8 core on the 1st ccd with 4 cores on the second CCD. 6+6 = 8+4

It never is. It could be if AMD had decided to go down that route, which would be more beneficial to consumers, but it's always a 6+6 in reality.

Even the 5600X and 5800X had some examples of two 3+3/4+4 CCDs, without AMD informing consumers or changing the product name/price. It was news a while back. The full 8 core CCDs are reserved for the higher chips or the server chips. x900 is always a defect bin.

Dual-CCD Ryzen 5 5600X and Ryzen 7 5800X In the Wild

Certain AMD Ryzen 5 5600X and Ryzen 7 5800X processors are physically based on a dual-CCD design, according to an investigative report by Igor's Lab and Yuri "1usmus" Bubliy. The 5600X and 5800X are normally meant to be single-CCD processors owing to their core-counts. Based on the "Vermeer"...

www.techpowerup.com

A lot of people thought the 7900X3D (an even more pointless product) was going to be 8+4, for obvious reasons, but that isn't either.

https://www.reddit.com/r/Amd/comments/11eoeh0

 

[Vya Domus]

The CCD discussion is ridiculous, the guy literally posted a TPU chart where the difference between a 6 core CCD CPU and an 8 core one was 0.2%. I don't know if this is just autism or an ultra dedicated troll.

The AM4 coolers don't fit at the AM5 socket. No matter if an original or individual backplate.

I literally used a cooler from an AM4 system to an AM5 one, as long as the backplate and clips are all the same it will fit.

 

[tabascosauz]

The CCD discussion is ridiculous, the guy literally posted a TPU chart where the difference between a 6 core CCD CPU and an 8 core one was 0.2%. I don't know if this is just autism or an ultra dedicated troll.

Are you done with these stupid insults? Ready to get back on topic now instead of this idiotic beef you have with each other?

I guess my cleanup earlier wasn't noticed, my bad. I'll be more vocal about it next time.

 

[gurusmi]

I literally used a cooler from an AM4 system to an AM5 one, as long as the backplate and clips are all the same it will fit.

The AM4 screws are in general not long enough to fit on an AM5. You will miss around 5mm/0,2Inch to get an AM4 cooler on a AM5 socket. I have both sets for a HK Heatkiller 4 and also a EKWB Velocity Cooler here. Is it so hard to understand that there is still a bit of the thread missing?

 

[lawood]

This is an interesting discussion.

I'm wary of dual ccd chips.
We can look to the abysmal perfomance from the 7900x3d compared to its peers, having only 6 cores available will hurt performance down the line.

 

[the54thvoid]

The thread was created to discuss a new build, not just the CPU. That point has been flogged to death. Please don't regurgitate what's already been said - it simply keeps an argument going, and it's not in any way helpful to the thread.

Let the OP chime back in with some feedback.

 

[joepacelli]

Actually while the thread has taken a slight detour it has allowed me to get a better look at the AMD chips. I started doing more research on CCD/CCX. In the mean time I'm got a docking station which allows me to connect my laptop to my Dell U4919W monitor.
While I'm more of an AMD fan the laptop is an Intel i7-13800H which is 14 cores and 20 threads.
It has 64Gb
And a 2Tb NVMe

So I'm using it as my development system at home for now while I do more research.
This PC lasted 7 years
My prior PC was 10 years
I try to get the mid-range
7950X while this is a nice CPU, too expensive
And the 7900X was 12 cores - 24 threads which I felt was something that could last me 5-7 years again
I also changed the memory to 64Gb, instead of 32
Still flip flopping on whether to do
3 x 1tb
or
1 1tb and 1 2tb

I also recently purchased a NAS storage system, Terra-master F2-212 with 2 8tb drives in RAID
The drives arrived the same day my PC died and the Terra-master unit came the next day.
Luckily I was able to extract the data from my drives since I had an external reader.

 

[dgianstefani]

Actually while the thread has taken a slight detour it has allowed me to get a better look at the AMD chips. I started doing more research on CCD/CCX. In the mean time I'm got a docking station which allows me to connect my laptop to my Dell U4919W monitor.
While I'm more of an AMD fan the laptop is an Intel i7-13800H which is 14 cores and 20 threads.
It has 64Gb
And a 2Tb NVMe

So I'm using it as my development system at home for now while I do more research.
This PC lasted 7 years
My prior PC was 10 years
I try to get the mid-range
7950X while this is a nice CPU, too expensive
And the 7900X was 12 cores - 24 threads which I felt was something that could last me 5-7 years again
I also changed the memory to 64Gb, instead of 32
Still flip flopping on whether to do
3 x 1tb
or
1 1tb and 1 2tb

I also recently purchased a NAS storage system, Terra-master F2-212 with 2 8tb drives in RAID
The drives arrived the same day my PC died and the Terra-master unit came the next day.
Luckily I was able to extract the data from my drives since I had an external reader.

There's no downside to 1+2TB drives over 1+1+1. 2TB drives aren't twice as expensive as 1TB ones.

That way you have an extra slot if you want to add more storage later. I'd still suggest avoiding 1TB drives, it's not that much capacity in 2024 especially if you keep your systems for a decade and 2TB drives aren't that much more expensive.

 

[Chrispy_]

Don't buy a 7900X it's a six core in disguise.

That's only even partially true for gaming, and only then in some games if you use Windows 10 rather than Windows 11 with the updated scheduler.

For a workstation focus, it's dramatically superior to a 7800X3D. Encodes, compiles, and renders are going to be a good 30-40% faster on the 7900X. Honestly, if you can find it just get the vanilla 7900 for less than the cost of the 7800X3D - in my experience they run damn near identically to the 7900X once you enable PBO or set the TDP to match manually. Plus, you get a backup cooler that you can flip on eBay for $25 or so if you don't have any use for it.

 

[joepacelli]

Isn't the 7900 also 65W vs 170W for the 7900X.
Price difference on NewEgg is $399 vs $423
and on Amazon it's actually $398 vs $391

So the 7900X is cheaper on Amazon.
It comes down to do I want higher TDP
Operating Freq is 3.7/5.4max vs 4.7/5.6max

 

[Vya Domus]

Isn't the 7900 also 65W vs 170W for the 7900X.
Price difference on NewEgg is $399 vs $423
and on Amazon it's actually $398 vs $391

So the 7900X is cheaper on Amazon.
It comes down to do I want higher TDP
Operating Freq is 3.7/5.4max vs 4.7/5.6max

You can just turn PBO on and they become nearly identical if the cooling is good enough, my 7900 runs at 5.1-5.3 Ghz under sustained all core load. If it's cheaper then buy a 7900X but I still think it's a better idea if you want to ever resell it to pick the 7900.

 

[Chrispy_]

Isn't the 7900 also 65W vs 170W for the 7900X.
Price difference on NewEgg is $399 vs $423
and on Amazon it's actually $398 vs $391

So the 7900X is cheaper on Amazon.
It comes down to do I want higher TDP
Operating Freq is 3.7/5.4max vs 4.7/5.6max

You can just turn PBO on and they become nearly identical if the cooling is good enough, my 7900 runs at 5.1-5.3 Ghz under sustained all core load. If it's cheaper then buy a 7900X but I still think it's a better idea if you want to ever resell it to pick the 7900.

This is actually what I did ordering for six workstations today; 7900X was £5 less than the 7900 and I'm not using the stock cooler on the 7900 since I have a box of unused AMD coolers.
The difference between the two models is minimal, you can run a 7900X at 65W and you can run a 7900 at 170W - the difference in clock speeds will be more down to silicon lottery than what exact model it is.

 

[Vya Domus]

7900X will have a higher single core boost out of the box, though you can get the 7900 to boost pretty close as well, mine does 5.5 Ghz, it's pretty much the only reason you'd want a 7900X over a 7900.

I should say a 7900X or 7900 with PBO will need a good 360mm or 280mm AIO if you want to get the most out of it.

 

[Franz]

Windows 11 with the updated scheduler.

This affect olders cpus too? Its possible to get better performance?

 

[Vya Domus]

This affect olders cpus too? Its possible to get better performance?

This affects all CPUs to varying degrees depending on their topology, there is no one optimal way to link cores together in a processor (other than giving each core a direct link to every other core which is not feasible), there will always be a variable latency when threads communicate from different cores even if the CPU is monolithic.

This isn't the big issue people make it out to be, don't bother with it.

 

[the54thvoid]

This affects all CPUs to varying degrees depending on their topology, there is no one optimal way to link cores together in a processor (other than giving each core a direct link to every other core which is not feasible), there will always be a variable latency when threads communicate from different cores even if the CPU is monolithic.

This isn't the big issue people make it out to be, don't bother with it.

In the TPU review, W1zzard noted the 2nd CCD (or whatever) ran at marginally lower clocks. So there is a performance hit on the parts that operate this way, compared to those that don't. It's why I bought an 8 core Ryzen - to avoid such complex interoperability.

And, FTR, given recent thread developments, please don't shadow bait other members (your final sentence of your post).

 

[Vya Domus]

2nd CCD (or whatever) ran at marginally lower clocks. So there is a performance hit on the parts that operate this way

Performance hit compared to what ? All multi CCD CPUs work like that, the first CCD on 7900X clocks higher than the single CCD 7700X for example and the 7900X still has more cores and higher performance in multithreading. The clock speeds are unrelated to AMD's choice to use chiplets and it's issues. Intel CPUs have effectively the same behavior with the lower clocked e cores (arguably much bigger issue). Btw, the differences between the CCDs are of 1-200 mhz, less than 5% of what these cores run at.

please don't shadow bait other memberst).

I am not baiting anyone, it's the truth, this stuff really doesn't matter for all intents and purposes. Even Intel's e cores rarely have a significant impact worth considering. The only CPUs that ever had a big problem with this were those first gen threadrippers.

 

[Princess Garnet]

The only point I made was that the 7900 is just a six core, with another six core bolted on (but accessing those extra cores comes with a cost).

I guess I'm just looking at this from a practical standpoint.

Consider this...

If one doesn't need more than 8 cores, you shouldn't be looking above Ryzen 7 to begin with, right? The whole CCD thing aside, it would still be better to go for the Ryzen 7 just from a performance or cost perspective alone. That is, for those who don't utilize more than 8 cores, the X3D Ryzen 7 will outperform the x900 base model for plus or minus the same cost, or the base Ryzen 7 will be cheaper than the x900 base model and offer the same performance. So the x900 is just a waste of performance or money if you don't need more than 8 cores.

If you can use more than 8 cores, none of that CCD stuff matters either because the Ryzen 9 is still going to vastly outperform an 8 core CPU in those situations.

Yes, non-monolithic CPUs have latency penalties. I wonder if we might want to get used to it, because it seems like that's going to increasingly be the future for chips in general.

You seem to be fixating on something that seems rather arbitrary to me in order to pick on the 7900 in particular, when said thing isn't even exclusive to the 7900, so I was wondering what the angle was. The x950 has the same consideration, no? If you want to be thorough, every Ryzen pre-5000 series had two CCXs per CCDs and had penalties from that (making the CCXs equal the number of cores on the CCD was part of where Zen 3 got its performance uplift from). Are we supposed to say the majority of the Ryzen lineup is just not good because of this then, in the face of the benchmarks that show they're fine despite it? That seems questionable to me.

I have no horse in this race to defend the x900 CPUs. I've constantly been answering the "5800X3D or 5900X" questions when the first X3D CPU came out from people wondering which was better at the same price, and the answer was always obvious; it's the 5800X3D, unless you can utilize over 8 cores then it's the 5900X, and most people probably don't need higher core counts (my presumption is if they do, they'd most likely know and wouldn't be asking that to begin with). So if anything, I'd be partial against the x900 series for most users, but not because any CCD things or because the x900 is bad entirely. Instead it's because it's not a CPU that best fits what most people need. It's niche, but fine.

I absolutely agree with you on the 7900X3D in particular though. I have no idea why that CPU exists. A 7600X3D would have been far more viable in my mind. The 7950X3D justifies itself at least, but the 7900X3D never should have released (my opinion). But the base 7900/X are fine.

 

[Vya Domus]

I have no idea why that CPU exists.

It's faster than a regular 7900X in games and slightly worse in productivity. It serves the role it was made for, it's very niche but it has it's purpose.