It was always clear there were issues which is why we never got the Vcache 5900X which was the cpu AMD showcased when revealing the tech. Maybe the 4ghz they used in the demo was all it could do so they had to revert to a 5800X3D with 2/3 of the cores and half the L3 cache to actually make it work but even then 4.5 was the best speed they could get.
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AMD confirms Ryzen 7 5800X3D launches this spring, Zen4 Raphael in 2H 2022
- Thread starter Dave2150
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I remember when Intel fans were hypeing new motherboards for every new skylake generation lol, clock alone isn't important, the only important thing is performance, this is gaming cpu so no one will buy it for productivity.
Well have to see what happens, it could be that curve optimizer and the voltage and clock control is also disabled
Caporegime
Allowing the 5800X to consume more than its 105 Watts makes it run too hot to boost higher. Otherwise known as "PBO overclocking"
The correct way to overclocking is to use a negative curve optimiser which reduces the power consumption and then use that headroom on the boost clock override.
Caporegime
I should probably explain it.....
The 5800X has a single CCD at 105 Watts, a 5950X has 2 CCD's at 105 watts, or about 55 watts for each CCD.
The heat density is a lot higher on the 5800X, there is no room for a higher power overclock, hence using a negative curve + boost override, that way you can get to 4.8 - 5.1Ghz, you can use PBO on the 5950X because all you're doing is allowing each CCD to run at 100 Watts + and get to the same 4.8Ghz +, its how you get 32,000 Points in R23, literally double a 5800X. Because its two 105 watt 5800X's.
The 5800X has a single CCD at 105 Watts, a 5950X has 2 CCD's at 105 watts, or about 55 watts for each CCD.
The heat density is a lot higher on the 5800X, there is no room for a higher power overclock, hence using a negative curve + boost override, that way you can get to 4.8 - 5.1Ghz, you can use PBO on the 5950X because all you're doing is allowing each CCD to run at 100 Watts + and get to the same 4.8Ghz +, its how you get 32,000 Points in R23, literally double a 5800X. Because its two 105 watt 5800X's.
Soldato
You were one of the people who said AMD was just meeting a TDP target and that we could overclock:
It doesn't mention "Unlocked for Overclocking" on AMDs own product page whereas all the other ryzen CPUs say this.
https://www.amd.com/en/products/cpu/amd-ryzen-7-5800x3d
Good find, that's probably as good an indicator as any at this point
we can only speculate on the reasons why; I suspect the heat density is right at its thermal limits with current cooling and perhaps amd testing showed if they enable pbo the chip very quickly overheats and gets damaged
Soldato
I assume the FCLK will still be able to go beyond 1600?
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Could preventing overclocking be damage control against the Zen 4 release? I.e. if this chip does happen to be a significant step up in gaming and Zen 4 only delivers marginal gains above that, it may sour the Zen 4 release.
Soldato
I think they asked for this to ensure there aren't masses of heating failures, thus damaging the 3D stacked marketing image for future cpus.
Someone WILL end up overclocking it to see what happens but OCing the 3d Stuff won't be an option I'd say until the 7th or 8th generation. AMD first need to iron out flaws and refine designs as this is a new type of CPU for mainstream, stopping OCing ability is just a precaution Id think at this stage.
Someone WILL end up overclocking it to see what happens but OCing the 3d Stuff won't be an option I'd say until the 7th or 8th generation. AMD first need to iron out flaws and refine designs as this is a new type of CPU for mainstream, stopping OCing ability is just a precaution Id think at this stage.
Soldato
Allowing the 5800X to consume more than its 105 Watts makes it run too hot to boost higher. Otherwise known as "PBO overclocking"
The correct way to overclocking is to use a negative curve optimiser which reduces the power consumption and then use that headroom on the boost clock override.
Even for the B2?
Caporegime
Yes.
Confirmed by overclocker and creator of various ryzen overclocking tools , the heat is a problem that's why OC is disabled in bios, stacked cache is causing high heat density and officially speaking AMD doesn't want the user tweaking the chip
https://mobile.twitter.com/1usmus/status/1501889826848755714
He also says (just his opinion) that Zen 4 won't launch with stacked cache
https://mobile.twitter.com/1usmus/status/1501889826848755714
He also says (just his opinion) that Zen 4 won't launch with stacked cache
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Soldato
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A failed experiment to some extent.
Either need lower power draw and voltages or different forms of cooling; heat rising through a stack of transistors isn't a good idea - that's why Intel hasn't bothered stacking yet, it's working on and waiting for next gen cooling to catch up - with stacking you need to be able to cool between the layers if you want to get the best performance from it, can't just stick a passive IHS on top of the top layer and expect great heat transfer
Soldato
It certainly doesn't seem to have worked as well as I had hoped, but if it's performance is good for it's price relative to the competition, I wouldn't call it a failure.
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Soldato
Considering it's AMD's first gen with stacked cache I had a feeling there would be a fair few trade-offs. They should've kept this on the server/professional side of things and iron out the issues before bringing it to the mainstream market. I think they jumped on this too fast in an attempt to stay ahead of Intel.