Colstan
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AMD has just launched their first Zen 4 CPUs with V-Cache, the 7950X3D and 7900X3D. It is notable that the 7800X3D won't ship until April 6th.
Relevant specs:
7950X3D: 16C/32T, 128GB L3, 4.2Ghz, Boost to 5.7Ghz.
7900X3D: 12C/24T, 128GB L3, 4.4Ghz, Boost to 5.6Ghz.
7800X3D: 8C/16T, 96GB L3, 4.2Ghz, Boost to 5.0Ghz.
Pricing for the models are $699, $599, and $449 USD, respectively. This is between a $100 to $180 premium over the non-X3D models.
AMD only sent out samples of the 7950X3D to reviewers. As usual, Gamer's Nexus had the most comprehensive review.
The 7950X3D and 7900X3D ship with the L3 connected to the left CCD, meaning that only half the cores can directly take advantage of that feature. In the video, Steve calls the launch date and performance of the 7950X3D and 7900X3D "suspect", because the 7800X3D has been delayed for another five weeks. All of the cores in the 7800X3D are able to fully utilize the added L3 without latency issues.
The CCD with access to the L3 runs at a lower clock than those in the other CCD. The cores without V-Cache can still access the L3, but incur a latency crossing the fabric, which AMD has attempted to work with Microsoft on improving. It's also important to enable AMD's extra driver features, or else performance will suffer. At full all-core load, the 7950X consumes 156W, compared to the 13900K's 295W.
On top of that, by disabling half the cores, they found that they actually get better performance. Along those lines, Hardware Unboxed "simulated" a 7800X3D in their review. Keep in mind that this isn't actual shipping silicon, and just a way for them to estimate the performance of the 7800X3D.
In terms of actual games, CPU heavy titles like Shadow of the Tomb Raider see up to a 25% uplift. With GPU intensive games, like Cyberpunk, the gains are negligible, and you really need a 4090 to see any benefit. There are outliers, like CSGO, which perform worse than the base 7950X.
Concerning content creation and non-gaming tasks, the V-Cache models see little to no benefit.
The delay in releasing the 7800X3D is certainly questionable. I think it stands to reason that AMD is trying to see how many customers are willing to pony up the cabbage for one of the more expensive models, before the 7800X3D ships. The 7800X3D model being the one that every gamer would likely purchase.
I think it would have been better to market the high core count models toward content creators which also happen to game. If AMD were being honest about this, they should launch them all at the same time. Instead, they are trying to market all three as gaming CPUs, even though games don't take advantage of the higher core count.
Also, AMD gimped the clock boost by 700Mhz between the 7950X3D and 7800X3D. Reviewers speculate this is a way of segmenting the line, in order to justify the existence of the higher end models.
My take is that if you are using these for non-gaming tasks, then it's a hard pass. If you are a gamer, wait for the 7800X3D model coming in April.
Relevant specs:
7950X3D: 16C/32T, 128GB L3, 4.2Ghz, Boost to 5.7Ghz.
7900X3D: 12C/24T, 128GB L3, 4.4Ghz, Boost to 5.6Ghz.
7800X3D: 8C/16T, 96GB L3, 4.2Ghz, Boost to 5.0Ghz.
Pricing for the models are $699, $599, and $449 USD, respectively. This is between a $100 to $180 premium over the non-X3D models.
AMD only sent out samples of the 7950X3D to reviewers. As usual, Gamer's Nexus had the most comprehensive review.
The 7950X3D and 7900X3D ship with the L3 connected to the left CCD, meaning that only half the cores can directly take advantage of that feature. In the video, Steve calls the launch date and performance of the 7950X3D and 7900X3D "suspect", because the 7800X3D has been delayed for another five weeks. All of the cores in the 7800X3D are able to fully utilize the added L3 without latency issues.
The CCD with access to the L3 runs at a lower clock than those in the other CCD. The cores without V-Cache can still access the L3, but incur a latency crossing the fabric, which AMD has attempted to work with Microsoft on improving. It's also important to enable AMD's extra driver features, or else performance will suffer. At full all-core load, the 7950X consumes 156W, compared to the 13900K's 295W.
On top of that, by disabling half the cores, they found that they actually get better performance. Along those lines, Hardware Unboxed "simulated" a 7800X3D in their review. Keep in mind that this isn't actual shipping silicon, and just a way for them to estimate the performance of the 7800X3D.
In terms of actual games, CPU heavy titles like Shadow of the Tomb Raider see up to a 25% uplift. With GPU intensive games, like Cyberpunk, the gains are negligible, and you really need a 4090 to see any benefit. There are outliers, like CSGO, which perform worse than the base 7950X.
Concerning content creation and non-gaming tasks, the V-Cache models see little to no benefit.
The delay in releasing the 7800X3D is certainly questionable. I think it stands to reason that AMD is trying to see how many customers are willing to pony up the cabbage for one of the more expensive models, before the 7800X3D ships. The 7800X3D model being the one that every gamer would likely purchase.
I think it would have been better to market the high core count models toward content creators which also happen to game. If AMD were being honest about this, they should launch them all at the same time. Instead, they are trying to market all three as gaming CPUs, even though games don't take advantage of the higher core count.
Also, AMD gimped the clock boost by 700Mhz between the 7950X3D and 7800X3D. Reviewers speculate this is a way of segmenting the line, in order to justify the existence of the higher end models.
My take is that if you are using these for non-gaming tasks, then it's a hard pass. If you are a gamer, wait for the 7800X3D model coming in April.