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AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

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Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#181

Post by LoganDark »

hnuser123456 wrote: post #173
somebodythere wrote: post #151

Earlier quoted context omitted.

I don't think the average Factorio gamer is going to know that they should do this or how. They will just know that their new CPU which was supposed to have better gaming performance is doing very, very poorly.

You are talking about Factorio players who specifically bought an 3D-L3 CPU, I would guess awareness would pretty high, personally...

> You are talking about Factorio players who specifically bought an 3D-L3 CPU

Factorio players don't necessarily know anything about computers. And you don't know if they bought this CPU or if it came with their fancy prebuilt.

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#182

Post by guilamu »

perihelions wrote: post #50
drewg123 wrote: post #45

Earlier quoted context omitted.

When they manually forced it onto the CCD with 3D-Vcache, they saw a 100% speedup: " As we can see in our Factorio benchmark, we saw massive gains of over 100% when forcing the Ryzen 9 7950X3D to use the CCD with the 3D V-Cache as opposed to letting AMD's PPM Provisioning and 3D V-Cache Optimizer drivers do their thing automatically. "

Oh good catch! I didn't read that far. It's on page 11: https://www.anandtech.com/show/18747/the-amd-ryzen-9-7950x3d... ( "Conclusion ")

5800x3D has a single CCD so no need to choose which CCD to use.

The interesting one will be the 7800X3D.

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#183

Post by mosquitobiten »

sixothree wrote: post #73
satvikpendem wrote: post #70

I wish the 64 core Threadrippers were still available for a decent price for HEDT, it's all Epyc or Threadripper Pro which are much more expensive for minimal increase in power over the 3990x.

RIP threadripper workstations support.

I think they scaled it down to the actual size of the market which is pretty small and that might look like what you're saying.

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#184

Post by mosquitobiten »

Firther wrote: post #121
Prunkton wrote: post #90

Earlier quoted context omitted.

the Linux test leaves me quiet confused how to pick my next linux gaming cpu. On the one hand side Gamers Nexus is making a point [0] (there are on/off performance charts later in the video) why it is super important to install the latest windows drivers + special windows gaming software to make use of the heterogeneous architecture. On the other hand side the linux tests are much better then I would expected since i…

It's not quite the same out of the box experience (after making sure you have the latest chipset drivers, use the balanced power plan and NOT the performance plan, and have Xbox Game Bar..), but it's possible to force certain processes and executables to run on specific CPU cores in Linux using taskset and verify that they're running on the correct cores. It will be a little tedious if you play a lot of games on Stea…

What about a VM with GPU pass-trough? Let's say I have plenty of storage and just create different VMs with selected distro or winXI that have certain games. Could that also be an option? Just drag and drop the appropriate game in the VM storage?

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#186

Post by arprocter »

carom wrote: post #179
arprocter wrote: post #58

Earlier quoted context omitted.

If you're on a 3700X you'll need a new board and RAM for AM5 Assuming your motherboard has video outputs it'll be much cheaper to stay on AM4 and throw in a 5700G

I just fell into this hole. Started a rebuild and the only thing moving to the new computer is my 3090.

Yeah - I was debating switching from 5600X to 5800X3D, but it probably makes more sense to wait for the AM5 dust to settle and redo the whole thing

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#187

Post by kllrnohj »

mort96 wrote: post #79
kllrnohj wrote: post #75

Earlier quoted context omitted.

Or buy an X3D that's homogeneous, like the 5800X3D or upcoming 7800X3D. I have no idea why AMD made the 7950X3D be this weird 50/50 split. Why not make both CCDs have 3D V-cache and make it the true halo part it should be? Then cut costs with the 7900X3D?

The added cache isn't free; the CCD with vcache runs at a significantly lower clock speed. If every task was always put on the most appropriate CCD, the heterogeneous approach is pretty much a direct advantage, as frequency-sensitive workloads get high frequencies and cache-sensitive workloads get lots of cache. Whether it will ever get good enough at picking CCD remains to be seen though.

Perhaps but I have no idea how any scheduler can possibly figure out if a workload is frequency or cache sensitive. The current strategy seems to be "if game, use cache, else use frequency" and it sorta works OK-ish? Although then there's games that aren't detected right (like Factorio) and it's then a terrible result.

But if you look at single threaded results with it set to "prefer cache" it's not really that much slower. Yes you'd have a flagship with lower single-threaded Cinebench results, but I mean that also happens with pretty much every HEDT platform and nobody bats an eye at that. The results are still a significant step beyond the 5000 series single core results.

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#188

Post by kllrnohj »

goosedragons wrote: post #81
kllrnohj wrote: post #75

Earlier quoted context omitted.

Or buy an X3D that's homogeneous, like the 5800X3D or upcoming 7800X3D. I have no idea why AMD made the 7950X3D be this weird 50/50 split. Why not make both CCDs have 3D V-cache and make it the true halo part it should be? Then cut costs with the 7900X3D?

Because the added 3D V-cache increases heat. That's also why the X3D variants have lower clocks than the non-X3D versions. Two CCDs with V-cache is apparently too hot.

That doesn't pass a sniff test at all. The 7950X3D TDP is 120W vs. the 7950X's 170W, even ignoring that modern TDP is a dumb metric actual power consumption also backs that up - the 7950X3D uses signiifcantly less power than a 7950X. And, as an expected result of that, the 7950X3D also runs cooler as a result than the 7950X does. There's no evidence to support a thermal or power limit here.

And it wasn't that different for the 5800X vs. 5800X3D, either. The extra cache at the same TDP seems to translate to around a 200mhz clock speed loss, temperatures otherwise the ~same.

Cache is also not very power hungry in general. Perhaps you meant it was a thermal barrier but again see above - all evidence points to AMD having figured that part out, there's no hint of thermal constraints on either the previous nor current 3d v-cache parts.

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#189

Post by brucethemoose2 »

paulmd wrote: post #171
brucethemoose2 wrote: post #101

Earlier quoted context omitted.

Previously that wasn't the issue, the issue (according to AMD) was that there was a huge interchip communication bottleneck with the extra L3 on both chips. If thats fixed, then AMD is just being cheap :P

epyc has v-cache on every die on -X skus, doesn't it? it's fine https://www.anandtech.com/show/17323/amd-releases-milan-x-cp... > Critically, AMD has opted to equip all of their new V-cache EPYC chips with the maximum 768 MB of L3 cache, which in turn means all 8 CCDs must be present, from the top SKU (EPYC 7773X) to the bottom SKU (EPYC 7373X). Instead, AMD will be varying the number of CPU cores enabled in each CCD…

They very specifically said it was an interconnect issue. With the extra L3, adjacent dies made so many requests to each other's cache that it turned into a bottleneck, and this wasnt an issue on Milan X because its IO die is apparently beefier.

I cant find the source because I am on mobile and now google search is flooded with X3D chatter :/

Re: AMD releases a new flagship CPU for consumer market with 128M of L3 Cache

#190

Post by TacticalCoder »

arprocter wrote: post #58
TacticalCoder wrote: post #3

Does this 7950X3D have an iGPU? P.S: the table in TFA lists the 7700 as having the same 105W as the 7700X. I think that's a slight mistake and the 7700 is 65W max listed TDP instead. FWIW I'm considering a 7700 for I'm not ultra happy with my 3700X (one of the reason being it has no iGPU and I could find a passive GPU with a NVidia chipset, forcing me to use proprietary drivers in Linux and it's a major PITA for if I…

If you're on a 3700X you'll need a new board and RAM for AM5 Assuming your motherboard has video outputs it'll be much cheaper to stay on AM4 and throw in a 5700G

I think I'll just get rid of it (give it to the wife or something): there are several things I don't like about it. No USB-C port (sure I could add an adapter), only 1 Gb/s ethernet on the mobo, etc. I'm not even sure I can just put a 5700G in it without having the flashing mobo.

I'll probably build something around an Asus B650-Plus mobo: it's got USB-C stock, 2.5 Gbit/s ethernet, DDR5 (I know it's pricier and boots slower, but it's faster too), etc.

I'll reuse one of the NVMe .2 SSD I've got laying around so the whole build should set me back 1 K EUR (with 32 GB of DDR5), which is quite okay.

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