cpu question

[over 9000]

whats better value for money 7800x3d or 7900x3d? thanks

[Illusion of Progress]

If it's for games, the 7800X3D. It costs less and has similar performance. The 7900X3D is strange to even exist because the Ryzen 9 X3Ds only have v-cache on one of their two CCDs. That's fine for the 7950, but the 7900 is a pair of hex core CCDs, so the 7900X3D only has 6 v-cache cores instead of 8 like the 7800X3D.

In theory, the Ryzen 9 X3Ds are hybrids that trade only a bit of gaming and a bit productivity while being almost the best blend of both, but that sort of only applies for the 7950X3D. If you're doing gaming, a 7800X3D is better, and if you're doing productivity, a 7900/7900X is better.

In short, the 7800X3D, because if you have productivity needs on top of that, just go with the 7950X3D. The 7900X3D really has little reason to exist.

[over 9000]

Illusion of Progress lähetti viestin:

If it's for games, the 7800X3D. It costs less and has similar performance. The 7900X3D is strange to even exist because the Ryzen 9 X3Ds only have v-cache on one of their two CCDs. That's fine for the 7950, but the 7900 is a pair of hex core CCDs, so the 7900X3D only has 6 v-cache cores instead of 8 like the 7800X3D.

In theory, the Ryzen 9 X3Ds are hybrids that trade only a bit of gaming and a bit productivity while being almost the best blend of both, but that sort of only applies for the 7950X3D. If you're doing gaming, a 7800X3D is better, and if you're doing productivity, a 7900/7900X is better.

In short, the 7800X3D, because if you have productivity needs on top of that, just go with the 7950X3D. The 7900X3D really has little reason to exist.

0 productivity needs, just to grind games :D thank you for the answer

[Illusion of Progress]

Yeah, definitely the 7800X3D then. The 7950X3D has merit if you're looking to be fancy and step up to overkill, but the 7900X3D is actually a worse option. I'm wondering why AMD even made it. If it was a 8/4 configuration is might have made some sense.

[Bad 💀 Motha]

Yes the X3D on the 7900/7950 is just terrible due to how the chiplets work.

7700X or 7800X3D is the choice for Gaming.

Please note that if you do go with 7800X3D be sure to get a decent CPU cooler and also be mindful that the X3D CPUs are much pickier when it comes to which RAM you use.

[r.linder]

7800X3D outperforms the 7900X3D and 7950X3D most of the time because of the fact that AMD thought it was a good idea to put the 3D v-cache on only one of the two chiplets present in Ryzen 9 processors.

[Illusion of Progress]

r.linder lähetti viestin:

7800X3D outperforms the 7900X3D and 7950X3D most of the time because of the fact that AMD thought it was a good idea to put the 3D v-cache on only one of the two chiplets present in Ryzen 9 processors.

I remember being bewildered by this when they were first announced too, but over time I put thought into it and realized it was actually the better move to do it the way they did with mixed CCDs. AMD knew what they were doing here. They probably thought there was too small of a market for doing it on both CCDs, and they'd probably be right.

The v-cache isn't a complete net gain. It adds cost. It perhaps adds to cooling needs. And beyond those, it can actually detract from performance. While the v-cache itself almost never hurts performance, having it means the CCD needs to be clocked lower, so when something isn't cache or I/O bound, it just loses a small bit of performance due to that lower clock speed. Not much, no, but ultimately it's a "you're paying quite a bit more yet losing slightly on performance" and that's not an attractive offering.

The v-cache chips are primarily marketed towards games as that's a prime use case that benefits from it, and the gains far outweigh the losses there so the average performance is still higher. So it's a net gain there even if there are some losses, and a big enough part of the market finds that average uplift worth the extra cost. The 5800X to 5800X3D was like a, what, 15% to 20% uplift or so on average in games (and that average is dragged backwards a lot by "doesn't gain at all so losses some due to lower clock speeds" and "only gains a bit" but a significant portion of games gain well beyond that, and the minimums are raised even more than the average). People will pay for that even when the value is worse when it represents some of the fastest gaming performance you can get at the time.

So getting back to the Ryzen 9s, you have to ask what impacts there could be if both CCDs were v-cache equipped instead of one.

Well, you'd add to cost obviously, so would it be worth it?

In the case of the 7950X3D, you now have a CPU that's an extra bit slower relative to the 7950X in stuff that isn't v-cache benefiting. So it's marginally worse again in productivity. What about games? What games are going to see enough of a gain from more than eight cores that an even more expensive 7950XD would be appealing? It's now a less appealing CPU for both tasks. As an added bonus, if you know you have a game that doesn't benefit from v-cache, you can assign it to the non-X3D CCD and gain a bit of performance. You'd lose that too.

The 7950X3D is unironically better this way, at least in the present software world.

In the case of the 7900X3D, some things a bit different, but even this one probably comes out worse. The 7900XD is unappealing because it costs more than the 7800X3D but is worse in games. A lot of thie comes down to having two CCDs, and each being 6 cores instead of 8. So not only does it have the interconnect to contend with more often, but it has less v-cache cores outright. There's definitely room in the present market for a hex core X3D... but it would need to be on its own as a lower cost option, not found in an awkward higher cost option like the 7900X3D. But even with both CCDs equipped with v-cache, it's still dual CCDs and the extra four cores are waste in games more enough than not to outweigh that (plus the extra cost). It would still be a dead CPU almost nobody wants. In the future, when 12 cores can be on the same CCD and more games need above 8 cores, maybe things change.

So ultimately in both cases you end up with costlier CPUs that are worse than the present ones. They would be less appealing and worse off for it.

There is a similar reason Intel's top SKUs would be worse if all the e-cores went away and were replaced with P-cores. There's not many things that need that many P-cores, and for the things that scale "infinitely", the e-cores provide better supplementary performance for the space they require. As it is, some gamers tend to disable those and they sometimes see increases in performance (scheduling conflicts?), which suggests the remaining 8 cores are plenty for games and more would be too niche right now.

Also, sorry for the long thoughts. I just found your comment interesting because I had the same exact "wait, why only half..." reaction when they were first announced, but over time I have come to realize AMD certainly knew what they were doing here (same as how Intel's mixed approach has its benefits).

[(415!)Fle@B@gL@ne]

I'm 1440P 165Hz IPS GSYNC was thin-film changing by at 1440P no need why 130+ 150+fps

i9 10900k 10@5.125
32GB DDR4 PC3000
3090RTX Gaming OC Gigabyte 2100@9875
2 1TB NVME M.2
1000WATT

[Bad 💀 Motha]

RMJ lähetti viestin:

I would never build an AMD PC, I know too much about them -GO Intel. BUT use AMD gpu they are superior to gefarse in many ways Ask anyone that owns UBI game Breakpoint and they try to run VULKAN on a gefarce , And this is just one example of GTX's limitations

VULKAN runs perfectly fine on NVIDIA GPUs. Even older ones like GTX 900 / 10 series.

I'm using 3080 Ti w/ Vulkan in RDR2 and it runs better then any AMD GPU out there.

[Cathulhu]

To be fair, VULKAN runs fine on both nVidia and AMD GPUs, it entirely depends on how well VULKAN was implemented into the application.
I have experienced games that had issues while VULKAN was used, but i also had games that had issues with DX12.

[Cake]

Ryzen 7 7800x3D is much better, doesn't have latency between cores, some cases it can be faster than the Ryzen 9's 7900/7950x3D's

[Guydodge]

RMJ lähetti viestin:

I would never build an AMD PC, I know too much about them -GO Intel. BUT use AMD gpu they are superior to gefarse in many ways Ask anyone that owns UBI game Breakpoint and they try to run VULKAN on a gefarce , And this is just one example of GTX's limitations

i agree with you on AMD intel is a far more stable platform and the same applies to nvidia
i just got a AMD for the wife my first AMD gpu ever wont make that mistake twice it was
problematic right out of box seems they are as unstable as their cpu's

[over 9000]

Guydodge lähetti viestin:

RMJ lähetti viestin:

I would never build an AMD PC, I know too much about them -GO Intel. BUT use AMD gpu they are superior to gefarse in many ways Ask anyone that owns UBI game Breakpoint and they try to run VULKAN on a gefarce , And this is just one example of GTX's limitations

i agree with you on AMD intel is a far more stable platform and the same applies to nvidia
i just got a AMD for the wife my first AMD gpu ever wont make that mistake twice it was
problematic right out of box seems they are as unstable as their cpu's

hmm its just that rust performs the best using the 3d cpu chips, thats the only reason im inclined to go AMD.

[Ralf]

RMJ lähetti viestin:

I would never build an AMD PC, I know too much about them -GO Intel. BUT use AMD gpu they are superior to gefarse in many ways Ask anyone that owns UBI game Breakpoint and they try to run VULKAN on a gefarce , And this is just one example of GTX's limitations

From what i've read Navi is far inferior compared to nvidia if it comes to stability. drivers just aren't great.
I would get 10850k or 11700k with RTX3090, E-cores can cause stuters on 12/13/14th gen Intel similar to AMDip. Even if you disable them, latency is lower on 10/11th gen and whole PC feels more responsive.

[r.linder]

König lähetti viestin:

Guydodge lähetti viestin:

i agree with you on AMD intel is a far more stable platform and the same applies to nvidia
i just got a AMD for the wife my first AMD gpu ever wont make that mistake twice it was
problematic right out of box seems they are as unstable as their cpu's

hmm its just that rust performs the best using the 3d cpu chips, thats the only reason im inclined to go AMD.

I'd advise that you ignore the people that still trash AMD these days because their opinion is exactly that, an opinion, and it's not based on fact, it's based on a specific bad experience that isn't representative of 90%+ of users of the same product.

Latency and responsiveness for 7000 series was literally better than Intel's when it came out but that wasn't difficult to do because the hybrid P-core+E-core design was freaking stupid. CPUs with multiple core dies are always going to have more latency than a CPU with fewer or a single die, AMD had the same latency problems with Threadripper and Ryzen 9, still do in some instances but it's been greatly diminished as they improved the design.