Further specifications of AMD's EPYC Milan-X CPU lineup which will be powered by Zen 3 cores with vertical 3D V-Cache stacking technology have leaked out. The latest specs come from ExecuFix which reveal specific clock speeds and the most interesting feature of the Milan-X chips, the L3 cache.
AMD EPYC Milan-X CPU Specs Leak Out - 64 Zen 3 Cores, 280W TDP, & Insane 768 MB Thanks To 3D V-Cache Technology
The AMD EPYC Milan-X lineup is no mystery, we already saw the chips listed at several retailers & preliminary specifications were listed too. Now we know the exact core clocks and the amount of cache that the new Zen 3 chips with 3D V-Cache vertical chiplets stacking technology will offer for server customers.
AMD EPYC Milan-X server CPU lineup will consist of four processors. The EPYC 7773X features 64 cores and 128 threads, the EPYC 7573X features 32 cores and 128 threads, the EPYC 7473X features 24 cores and 48 threads while the EPYC 7373X features 16 cores and 32 threads. The models along with their OPN codes are:
- EPYC 7773X 64 Core (100-000000504)
- EPYC 7573X 32 Core (100-000000506)
- EPYC 7473X 24 Core (100-000000507)
- EPYC 7373X 16 Core (100-000000508)
The flagship AMD EPYC 7773X will rock 64 cores, 128 threads and feature a maximum TDP of 280W. The clock speeds will be maintained at 2.2 GHz base and 3.5 GHz boost while the cache amount will drive up to an insane 768 MB. This includes the standard 256 MB of L3 cache that the chip features so essentially, we are looking at 512 MB coming from the stacked L3 SRAM which means that each Zen 3 CCD will feature 64 MB of L3 cache. That's an insane 3x increase over the existing EPYC Milan CPUs.
The second model is the EPYC 7573X which features 32 cores and 64 threads with a 280W TDP. The base clock is maintained at 2.8 GHz and the boost clock is rated at up to 3.6 GHz. The total cache is 768 MB for this SKU too. Now interestingly, you don't need to have 8 CCDs to reach 32 cores as that can be achieved with a 4 CCD SKU too but considering that you'd need double the amount of stack cache to reach 768 MB, that doesn't look like a very economical option for AMD and hence, even the lower-core count SKUs might be featuring the full 8-CCD chips.
With that said, we have the EPYC 7473X which is a 24 core and 48 thread variant with a 2.8 GHz base and 3.7 GHz boost clock and a TDP of 240W while the 16 core and 32 thread EPYC 7373X is configured at a 240W TDP with a base clock of 3.05 GHz and 3.8 GHz boost clock and 768 MB of cache.
AMD EPYC Milan-X 7003X Server CPU (Preliminary) Specs:
| CPU Name | Cores / Threads | Base Clock | Boost Clock | LLC (3D SRAM) | L3 Cache (V-Cache + L3 Cache) | L2 Cache | TDP | Price (ShopBLT) | Price (MSRP) |
|---|---|---|---|---|---|---|---|---|---|
| AMD EPYC 7773X | 64 / 128 | 2.2 GHz | 3.500 GHz | Yes (64 MB per CCD) | 512 + 256 MB | 32 MB | 280W (cTDP 225W Down / 280W Up) | $9609.36 US | $8800 US |
| AMD EPYC 7763 | 64 / 128 | 2.45 GHz | 3.500 GHz | N/A | 256 MB | 32 MB | 280W (cTDP 225W Down / 280W Up) | $8616.41 US | $7890 US |
| AMD EPYC 7573X | 32 / 64 | 2.80 GHz | 3.600 GHz | Yes (64 MB per CCD) | 512 + 256 MB | 32 MB | 280W (cTDP 225W Down / 280W Up) | $6107.88 US | $5590 US |
| AMD EPYC 75F3 | 32 / 64 | 2.95GHz | 4.000 GHz | N/A | 256 MB | 32 MB | 225W (cTDP 225W Down / 240W Up) | $5312.39 US | $4860 US |
| AMD EPYC 7473X | 24 / 48 | 2.80 GHz | 3.700 GHz | Yes (64 MB per CCD) | 512 + 256 MB | 12 MB | 240W (cTDP 190W Down / 250W Up) | $4290.23 US | $3900 US |
| AMD EPYC 74F3 | 24 / 48 | 3.20 GHz | 4.000 GHz | N/A | 128 MB | 12 MB | 200W (cTDP 165W Down / 200W Up) | $3197.87 US | $2900 US |
| AMD EPYC 7373X | 16 / 32 | 3.05 GHz | 3.800 GHz | Yes (64 MB per CCD) | 512 + 256 MB | 8 MB | 240W (cTDP 190W Down / 250W Up) | $5137.38 US | $4185 US |
| AMD EPYC 73F3 | 16 / 32 | 3.50 GHz | 4.000 GHz | N/A | 128 MB | 8 MB | 190W (cTDP 165W Down / 200W Up) | $3874.10 US | $1565 US |
A single 3D V-Cache stack would incorporate 64 MB of L3 cache that sits on top of the TSV's already featured on existing Zen 3 CCD's. The cache will add upon the existing 32 MB of L3 cache for a total of 96 MB per CCD. AMD also stated that the V-Cache stack can go up to 8-hi which means a single CCD can technically offer up to 512 MB of L3 cache in addition to the 32 MB cache per Zen 3 CCD. So with a 64 MB of L3 cache, you can technically get up to 768 MB of L3 cache (8 3D V-Cache CCD stacks = 512 MB) which will be a mammoth increase in cache size.
3D V-Cache could just be one aspect of the EPYC Milan-X lineup. AMD might introduce faster clocks as 7nm continues to mature and we can see much faster performance from these stacked chips. It is also interesting that the OPN codes for these processors are ready which means that a launch by late 2022 is highly likely which would mean Milan-X might be the first chip to introduce 3D V-Cache. Expect more information in the coming months.
News Source: ExecutableFix
