A couple of reminders for people new to the thread. It's really easy to get focused on one number or even a few numbers, but that doesn't give us the full picture.
Reminder #1: AMD themselves puts the fMax for Ryzen 3000 series at 4.6GHz:
fMax slide from E3 presentation
Commentary:
You might get lucky and get +100, maybe +200 if you are lucky, but I fully expect all-core OCs past 4.5GHz to be prohibitively expensive in terms of voltage and cooling required. I expect PBO will mostly affect all-core turbos rather than boost the top end ST turbo like some seem to expect it to. It may actually work that way on something like the 3600 which is kept in check by its TDP and can benefit on both ST and MT clocks (see: process fMax # again? hint hint) but if you're expecting 4.9GHz on the 3950X I think you'll be disappointed. Remember that the ST Cinebench scores were basically within margin of error on the top-end SKUs with PBO enabled... that's pretty telling. It's also very telling that the one SKU which goes beyond 4.6GHz (at least on lightly threaded workloads) is the 3950X, and that launch isn't until September. Binning, binning, binning. And fMax.
^ all of the above probably doesn't matter, because a theoretical 15% IPC boost over a 4.35GHz 2700X would mean a 3950X would already perform at a hypothetical 5GHz 2700X's level, at least on some workloads. And that's without the frequency boost andL3 cache other minor improvements.
Reminder #2: Memory latency is only 1 factor in a multifactorial equation for gaming performance - L3 cache has doubled in Zen 2 and per AMD's numbers, this reduces effective memory latency by up to 33ns:
Gamecache slide from E3
Considering that PBO and auto-OC could potentially bring clocks on the Ryzen 3600 part up to 4.4GHz (barely below the fMax, at the cost of increased power consumption), I fully expect that to be the part valued most by people who want a good desktop CPU for gaming and everything else, but don't need more than 6c/12t.
Reminder #1: AMD themselves puts the fMax for Ryzen 3000 series at 4.6GHz:
fMax slide from E3 presentation
Commentary:
You might get lucky and get +100, maybe +200 if you are lucky, but I fully expect all-core OCs past 4.5GHz to be prohibitively expensive in terms of voltage and cooling required. I expect PBO will mostly affect all-core turbos rather than boost the top end ST turbo like some seem to expect it to. It may actually work that way on something like the 3600 which is kept in check by its TDP and can benefit on both ST and MT clocks (see: process fMax # again? hint hint) but if you're expecting 4.9GHz on the 3950X I think you'll be disappointed. Remember that the ST Cinebench scores were basically within margin of error on the top-end SKUs with PBO enabled... that's pretty telling. It's also very telling that the one SKU which goes beyond 4.6GHz (at least on lightly threaded workloads) is the 3950X, and that launch isn't until September. Binning, binning, binning. And fMax.
^ all of the above probably doesn't matter, because a theoretical 15% IPC boost over a 4.35GHz 2700X would mean a 3950X would already perform at a hypothetical 5GHz 2700X's level, at least on some workloads. And that's without the frequency boost and
Reminder #2: Memory latency is only 1 factor in a multifactorial equation for gaming performance - L3 cache has doubled in Zen 2 and per AMD's numbers, this reduces effective memory latency by up to 33ns:
Gamecache slide from E3
Considering that PBO and auto-OC could potentially bring clocks on the Ryzen 3600 part up to 4.4GHz (barely below the fMax, at the cost of increased power consumption), I fully expect that to be the part valued most by people who want a good desktop CPU for gaming and everything else, but don't need more than 6c/12t.
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