2,833 karma · joined August 19, 2009
The DDR5 will be registered DIMMs. The GPUs will be 600W paperweights with a custom form factor. Similarly the NICs and other PCI-E accelerators. The motherboards also adopt custom form factors to fit in racks. The hard drives will be using SAS connectors. The flash will be in E1.S form factors.
The server CPUs that you want for a home desktop or small server, high clock SKUs, will be in high demand.
Any savings for someone willing to build a system from second-hand server hardware will be eaten by using adapters or sourcing a rack.
I'm not saying you won't be able to make a slightly outdated frankenserver with more compute than you need, I'm saying that's not going to bring down prices for Grandma's machine that she needs working to check on her retirement account.
That's the S.
When the L3 sizes are different across CCDs the special AMD driver is needed to keep threads pinned to the larger L3 CCD and prevent them from being placed on the small L3 CCD where their memory requests can exploit the other CCD's L3 as an L4. The AMD driver reduces CCD to CCD data requests by keeping programs contained in one CCD.
With equal L3 caches when a process spills onto the second CCD it will still use the first's L3 cache as "L4" but it no longer has to evict that data at the same rate as the lopsided models. Additionally the first CCD can use the second CCD's L3 in kind reducing the number of requests that need to go to main memory.
The same sized L3s reduce contention to the IO die and the larger sized L3s reduce memory contention, it's a win-win.
https://www.phoronix.com/review/amd-3d-vcache-optimizer-9950...
I'm an advocate of sticking a $5 16Gb Optane stick from eBay on a $10 M.2 to PCIe 1x adapter from eBay. Set it up as swap in Windows or Linux. Or pay $200 for a 16GB stick of DDR5.
[1] https://lilibots.blogspot.com/2020/04/starlink-satellite-dim...
Servers had a reason to spend for the 10G, 25G and 40G cards which used 4 lanes.
There are 10 Gigabit chips that can run off of one PCI-E 4.0 lane now and the 2.5G and 5G speeds are supported(802.3bz).