Review AMD Ryzen 9 7900X3D Review: 3D V-Cache's Forgotten Middle Child

Metteec

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Brian D Smith: I get your point, but the Intel i9-13900K (the competitor to the Ryzen 9 7900X3D) supports both DDR4 and DD5. Therefore, Paul's feedback on this particular issue is warranted. AMD's design decision to switch exclusively to DDR5 is a detractor to many buyers, including myself, who would have upgraded their CPUs but can't because they would have to invest in DDR5. Conversely, Intel has eased the transition its 12th generation processor by offering compatible motherboards with either DDR4 or DDR5.

I would guess that Intel's 14th generation will ditch DDR4 for good, but as of now, DDR4 compatibility is one thing that the i9-13900K has going for it over the Ryzen 9 7900X3D.

Disclosure: I hold positions in both Intel and AMD stock and use predominantly AMD products.
 
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I wonder how the upcoming single-CCD 7800X3D will perform. I like that it's a single-CCD CPU vs the dual-CCD in the 7950/7900X3D. If it can boost to 5.6GHz, despite the official boost rating only showing 5.0GHz, then that could potentially be the best of both worlds (gaming & application, when app not limited by # of cores).
 
Brian D Smith: I get your point, but the Intel i9-13900K (the competitor to the Ryzen 9 7900X3D) supports both DDR4 and DD5. Therefore, Paul's feedback on this particular issue is warranted. AMD's design decision to switch exclusively to DDR5 is a detractor to many buyers, including myself, who would have upgraded their CPUs but can't because they would have to invest in DDR5. Conversely, Intel has eased the transition its 12th generation processor by offering compatible motherboards with either DDR4 or DDR5.

I would guess that Intel's 14th generation will ditch DDR4 for good, but as of now, DDR4 compatibility is one thing that the i9-13900K has going for it over the Ryzen 9 7900X3D.

Disclosure: I hold positions in both Intel and AMD stock and use predominantly AMD products.
13th Gen supports DDR4 because it is socket compatible with 12th Gen. Making 13th Gen DDR5 only would have meant that Z690 (and other 12th Gen chipsets) only supported 1 CPU version. As of late Intel has made it such that chipsets support 2 generations of CPUs. When 12th Gen came out, it made sense for there to be DDR4 support as DDR5 was at a huge price premium. Fast forward to now and the price premium over DDR4 is much lower, still not 1:1 but..., so supporting 2 memory types is only for socket compatibility for Intel's standard 2 generations. Had Intel gone DDR5 only on 13th Gen we probably would have seen DDR5 prices drop much faster than they already are.
 
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Brian D Smith: I get your point, but the Intel i9-13900K (the competitor to the Ryzen 9 7900X3D) supports both DDR4 and DD5. Therefore, Paul's feedback on this particular issue is warranted. AMD's design decision to switch exclusively to DDR5 is a detractor to many buyers, including myself, who would have upgraded their CPUs but can't because they would have to invest in DDR5.
Agree with you for the most part, but this idea that DDR5 is a killer for any consumers and having to go with AMD (without choice) for Zen4/AM5 doesn't add up. DDR4 support for Intel's current 13th Gen ends with Raptor. (maybe a Raptor -s not known yet). Meteor or next desktop is exclusively DDR5. Add to that, that AMD will support maybe 3/4 new CPU's on the same socket. Intel don't do that. The cost upfront, of maybe 100-150, sure does make up for not having to upgrade on Intel every two years.

For what it's worth, I'd rather have a socket that lasts 4-5 years, and allow for simple drop in upgrades, that are and can be substantive.
 

DavidLejdar

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I am avoiding the 7900X3D. Some games like to use up to 8 cores (when they are available), and the 6+6 setup means that some workload gets directed to 2 additional cores on the second CCD. This doesn't mean a stutter-fest. But what's the point (for gaming as such), when the 7800X3D may actually deliver better gaming performance, having 8 cores with 3D V-Cache?
I would guess that Intel's 14th generation will ditch DDR4 for good, but as of now, DDR4 compatibility is one thing that the i9-13900K has going for it over the Ryzen 9 7900X3D.
I think it is fair to point out that the CPU goes only with DDR5. But it would also be fair to run some tests comparing gaming performance of e.g. the 13900K with DDR4 and DDR5, as the charts seem to be presenting the performance with DDR5 only, which then makes it a somewhat moot point to say: "And this one can use DDR4 as well, which is a huge plus.", without then elaborating whether a DDR4 rig does deliver the same performance as a cheaper CPU with DDR5 perhaps may, etc.
 

JamesJones44

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-No support for DDR4 memory

LOL...that's like saying a horse cannot use an elephant's saddle. Seriously, why even say that as a negative? Oh...it's Paul.

Agreed. Last year I could have argued it might have made sense considering DDR5 was running close to double the same GB size in DDR4, but that's not the case anymore. I just did a quick check for 32 GB of ram at DDR4-3200 and DDR5-4800 and it was a whopping $34 more for the DDR5 version (Corsair Vengeance 2x 16 GB, no RPG/LED)
 

Metteec

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I think it is fair to point out that the CPU goes only with DDR5. But it would also be fair to run some tests comparing gaming performance of e.g. the 13900K with DDR4 and DDR5, as the charts seem to be presenting the performance with DDR5 only,
Overclock3d did this test on the 13900K with DDR4 and DD5 and found the results a mixed bag. Some games, like Far Cry 6, actually ran slightly faster on DDR4, while others DDR5 had a slight advantage. Overall, the difference was rather inconsequential.
 

ottonis

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Back in the day, differences in pc hardware decided between a game being playable or unplayable.
Having a Pentium 90 vs a Pentium 60 could mean 30 fps vs 20 fps.
And using a 3dfx Voodoo accelerator board vs a Matrox Mystique (also called "the 3d decelerator") could mean 70 fps vs 12 fps.

Now, we have CPUs that can play games at 200 fps and those that can only do 160 fps.

That's not even a discernible difference, is it?

Are there even games out there, that will only be playable with these 3d-cash CPUs?
 
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Co BIY

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[QUOTE the extra $100 would add roughly 3% or less to the cost of a $3,000 to $4,000+ system suitable for this class of chip. ][/QUOTE]

I think this shows the best way to think about the value of these high end chips. How much more performance do you get compared to your total system cost. With this metric I think the high-end CPUs fair well compared to other components like premium motherboards.

The charts show pretty clearly that any of the chips $400 and up can game.

Can X3D bring gaming performance up cheaper than a GPU step up ?

Assume a 4070Ti with Ryzen 5/i5 baseline system. Is there more bang (FPS improvement) for the buck by stepping up to X3D CPU or getting a 4080 ? Looks like there could be in something like Flight Sim.
 

Co BIY

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I think AMD's pricing strategy hurts the reviews of their new chips.

Intel leads with a lower MSRP but seems to maintain that price point over the life of the chip.

AMD starts with a higher MSRP but later lets them float downward to a better competitive position on the market. But the high initial release price hurts the value calculation when the reviews are written. Very little will be written when the prices drop slowly in a hundred stores.
 
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MergleBergle

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-No support for DDR4 memory

LOL...that's like saying a horse cannot use an elephant's saddle. Seriously, why even say that as a negative? Oh...it's Paul.
LOL, I wondered the same thing when I saw the negatives in the review. Like, wtf, this is well established at this point. I suppose in fairness someone totally new to the website and tech in general might find that helpful.
 

imsurgical

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Brian D Smith: I get your point, but the Intel i9-13900K (the competitor to the Ryzen 9 7900X3D) supports both DDR4 and DD5. Therefore, Paul's feedback on this particular issue is warranted. AMD's design decision to switch exclusively to DDR5 is a detractor to many buyers, including myself, who would have upgraded their CPUs but can't because they would have to invest in DDR5. Conversely, Intel has eased the transition its 12th generation processor by offering compatible motherboards with either DDR4 or DDR5.

I would guess that Intel's 14th generation will ditch DDR4 for good, but as of now, DDR4 compatibility is one thing that the i9-13900K has going for it over the Ryzen 9 7900X3D.

Disclosure: I hold positions in both Intel and AMD stock and use predominantly AMD products.

Exactly, so it'll be okay then for Intel to only support DDR5 and not be called out on but for AMD it's ridiculous and a "Con" even though it's praised for being a "Pro" as a "Modern Platform"? It's exactly why Paul's review is questionable. Not to mention 12th and 13th Gen are decaying platforms as you're implying. It should not be a fault of the CPU itself when reviewed to use DDR5 when it's literally a newer platform with a future ahead of it still. By the time 14th Gen is out, then it won't be an issue for those who have DDR5 already for AMD or Intel's current offerings when they can reuse it, so why should it be listed as a con for the 7000 AMD's?
 
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PlaneInTheSky

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-No support for DDR4 memory

LOL...that's like saying a horse cannot use an elephant's saddle. Seriously, why even say that as a negative? Oh...it's Paul.

People don't like to throw $200 worth of DDR4 RAM in the trash, just to buy DDR5 for a 0.1% gain in performance.

If DDR5 resulted in real-world performance gains, maybe AMD would have a point. But that's not the case, all this is doing is adding cost for users and more e-waste.
 
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PlaneInTheSky

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Like, wtf, this is well established at this point. I suppose in fairness someone totally new to the website and tech in general might find that helpful.

So what if it's known, it doesn't mean it's not relevant anymore.

If a line of car models rusts, reviewers will mention it every single time on every single model. Because that's what reviews are about, judging a product. It's not about hiding flaws so products come out looking better than they actually are.

The cost of AM5 is abnormally high because you need to buy new memory and mobos are very expensive. It gets mentioned.

Reviewers aren't responsible for AMD's bonehead decisions, AMD is.
 
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imsurgical

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People don't like to throw $200 worth of DDR4 RAM in the trash, just to buy DDR5 for a 0.1% gain in performance.

If DDR5 resulted in real-world performance gains, maybe AMD would have a point. But that's not the case, all this is doing is adding cost for users and more e-waste.

That's not the point, AMD isn't the sole reason why DDR5 exists. You're deferring blame to them simply because they don't utilize DDR4 on their platform when Intel is going to eventually do the exact same thing at one point.
 

imsurgical

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So what if it's known, it doesn't mean it's not relevant anymore.

If a line of car models rusts, reviewers will mention it every single time on every single model. Because that's what reviews are about, judging a product. It's not about hiding flaws so products come out looking better than they actually are.

The cost of AM5 is abnormally high because you need to buy new memory and mobos are very expensive. It gets mentioned.

Reviewers aren't responsible for AMD's bonehead decisions, AMD is.

What a ridiculous analogy. Does DDR5 not work, do the motherboards not work? Rusting on a production line of cars is one thing because it involves the functionality and safety ability of the chassis. What's your actual point? That AM5 boards are expensive, DDR5 memory is expensive? It is what it is....at one point or another, for the cost of what was once new with DDR4, or a new socket type from Intel or AMD was also true of being costly. This is a review about a CPU, it's performance in the face of its competition, and it beats it in many regards. When Intel comes out with 14th gen, it's going to be the same dance again, they're going to take the crown, which is good competition for the consumer, but are people going to complain that it'll be a DDR5 only platform? I'm sure you won't because you're wearing goggles.
 
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