4 ms·

Individual cores on the 7950x are roughly twice as fast as what you have. If your work isn't massively multithreaded, then a 7950x will likely perform quite a b

Individual cores on the 7950x are roughly twice as fast as what you have. If your work isn't massively multithreaded, then a 7950x will likely perform quite a bit better than a Threadripper 3970x. (Though of course you won't be able to get more than 128GB RAM.) This is with clamping down TDP on the 7950x to roughly 110W. It's an absolute beast.

ciupicri 4y ago
Besides more RAM, 3970x also has proper ECC support.
- flumpcakes 4y ago
  And more PCIe lanes, compared to the consumer platforms with a measly 20/24 (which is basically one GPU and one NVMe full bandwidth).
- GeorgeWBasic 4y ago
  How is the ECC support deficient on later CPUs? I checked the docs, it does seem to be supported on the 7000x series.
  - ciupicri 4y ago
    The CPU is alright, but the motherboards are lacking. You can install ECC memory modules on them and the system will boot, but you don't know for sure if ECC is really working unless the motherboard reports memory status like how many errors were correct. See also https://news.ycombinator.com/item?id=34133995 https://news.ycombinator.com/item?id=34133995
skirmish 4y ago
Keep in mind that 128 GB barely works on AM5 (basically, EXPO/XMP doesn't, only regular JEDEC speeds, i.e. 4800 MT/s) [1] 2 sticks of RAM up to 64 GB is the fully functional maximum. [1] https://old.reddit.com/r/Amd/comments/xzj69v/is_anyone_running_128gb_with_am5/ https://old.reddit.com/r/Amd/comments/xzj69v/is_anyone_runni...
- karamanolev 4y ago
  Are you saying that 2x32GB is the max that allows for EXPO/XMP? I'm thinking about building a system like that and this is critical. Do you have any better resources that explore this more and test out different configurations?
  - skirmish 4y ago
    That's my understanding, yes. All my knowledge is from random Reddit threads however. Since I was scared off 128 GB by all those complaints, I built a 7950X system with 2*32GB memory, and it runs well/stable at its rated 6000 MT/s with EXPO on (also, AMD says 6000 MT/s is the sweet spot for AM5 memory interface, so I am happy). Motherboard: ASRock X670E Steel Legend RAM: G.Skill Trident Z5 Neo 64 GB (2 x 32 GB) DDR5-6000 CL30 Here is another thread I remember reading: https://old.reddit.com/r/hardware/comments/za0x0q/level1techs_is_128gb_of_ddr5_impossible_on_am5/ https://old.reddit.com/r/hardware/comments/za0x0q/level1tech...
    - injinj 4y ago
      That's what I got (7950x steel legend), except that I'm running 128GB memory at 4800. Here's my stream results (with the cpu in 105watt "eco" mode): $ wget https://www.cs.virginia.edu/stream/FTP/Code/stream.c $ gcc -O3 -fopenmp stream.c $ a.out Number of Threads counted = 32 Copy: 45571.7 Scale: 40672.0 Add: 45317.3 Triad: 42759.0 With array size 8,000,000 Copy: 31551.3 Scale: 30983.7 Add: 34403.6 Triad: 34484.1
      - skirmish 4y ago
        Interesting, didn't think memory speed will make so much difference but it did. 7950x X670E Steel Legend, standard mode, 2*32 GB = 64 GB RAM at 6000, CL 30. Array size = 1,000,0000 Copy: 61488.8 Scale: 55905.4 Add: 61320.2 Triad: 57706.5 Array size = 8,000,0000 Copy: 43631.0 Scale: 43062.7 Add: 46782.6 Triad: 46966.8
photoGrant 4y ago
I can't max out my PCI slots and run 256gb in quad channel, though.

ciupicri 4y ago

Besides more RAM, 3970x also has proper ECC support.

flumpcakes 4y ago
And more PCIe lanes, compared to the consumer platforms with a measly 20/24 (which is basically one GPU and one NVMe full bandwidth).
GeorgeWBasic 4y ago
How is the ECC support deficient on later CPUs? I checked the docs, it does seem to be supported on the 7000x series.
- ciupicri 4y ago
  The CPU is alright, but the motherboards are lacking. You can install ECC memory modules on them and the system will boot, but you don't know for sure if ECC is really working unless the motherboard reports memory status like how many errors were correct. See also https://news.ycombinator.com/item?id=34133995 https://news.ycombinator.com/item?id=34133995

skirmish 4y ago

Keep in mind that 128 GB barely works on AM5 (basically, EXPO/XMP doesn't, only regular JEDEC speeds, i.e. 4800 MT/s) [1] 2 sticks of RAM up to 64 GB is the fully functional maximum. [1] https://old.reddit.com/r/Amd/comments/xzj69v/is_anyone_running_128gb_with_am5/ https://old.reddit.com/r/Amd/comments/xzj69v/is_anyone_runni...

karamanolev 4y ago
Are you saying that 2x32GB is the max that allows for EXPO/XMP? I'm thinking about building a system like that and this is critical. Do you have any better resources that explore this more and test out different configurations?
- skirmish 4y ago
  That's my understanding, yes. All my knowledge is from random Reddit threads however. Since I was scared off 128 GB by all those complaints, I built a 7950X system with 2*32GB memory, and it runs well/stable at its rated 6000 MT/s with EXPO on (also, AMD says 6000 MT/s is the sweet spot for AM5 memory interface, so I am happy). Motherboard: ASRock X670E Steel Legend RAM: G.Skill Trident Z5 Neo 64 GB (2 x 32 GB) DDR5-6000 CL30 Here is another thread I remember reading: https://old.reddit.com/r/hardware/comments/za0x0q/level1techs_is_128gb_of_ddr5_impossible_on_am5/ https://old.reddit.com/r/hardware/comments/za0x0q/level1tech...
  - injinj 4y ago
    That's what I got (7950x steel legend), except that I'm running 128GB memory at 4800. Here's my stream results (with the cpu in 105watt "eco" mode): $ wget https://www.cs.virginia.edu/stream/FTP/Code/stream.c $ gcc -O3 -fopenmp stream.c $ a.out Number of Threads counted = 32 Copy: 45571.7 Scale: 40672.0 Add: 45317.3 Triad: 42759.0 With array size 8,000,000 Copy: 31551.3 Scale: 30983.7 Add: 34403.6 Triad: 34484.1
    - skirmish 4y ago
      Interesting, didn't think memory speed will make so much difference but it did. 7950x X670E Steel Legend, standard mode, 2*32 GB = 64 GB RAM at 6000, CL 30. Array size = 1,000,0000 Copy: 61488.8 Scale: 55905.4 Add: 61320.2 Triad: 57706.5 Array size = 8,000,0000 Copy: 43631.0 Scale: 43062.7 Add: 46782.6 Triad: 46966.8

photoGrant 4y ago

I can't max out my PCI slots and run 256gb in quad channel, though.