[SOLVED] Would 1.41250V Be Safe For Ryzen 3900x, No SMT?

Oxicoi

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Feb 7, 2017
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Hi,

I recently am trying to see if I can lessen some of the heat the 3900x gets when getting to such voltage and I understand that 95c is the limit for the 3900x. I also am aware that it could be somewhat pointless to overclock the 3000 series, but I might make my money worth something since AM5 is right around the corner, as well as potentially switching to a 5950x anyway.

So, I have my 3900x running 'SMT OFF' at 1.41250V with LLC Level 5 at 4.5GHz and during Cinebench R23 testing, I noticed it doesn't go in the 80's (into the high 70's it does) in temperature on a 360AIO. Idle temps are in high 40's.
To me, this seems awesome since the 3900x boosts only a few of single cores to 4.6GHz at like a 1.5V burst or something, so theoretically I am ~0.1V lower to 4.5GHz all-core.

Only thing I can't remember if it's the voltage that will cause degradation or the temperature at which the voltage is set to being way too high (which in this case it isn't all that bad).
Is this worth having? 12c/12t @ 4.5GHz all with 1.41250 LLC-5, SMT OFF?

Also, a question: Does SMT enable 12 more "virtual" threads? Is that what hyperthreading is?
 
Hi,

I recently am trying to see if I can lessen some of the heat the 3900x gets when getting to such voltage and I understand that 95c is the limit for the 3900x. I also am aware that it could be somewhat pointless to overclock the 3000 series, but I might make my money worth something since AM5 is right around the corner, as well as potentially switching to a 5950x anyway.

So, I have my 3900x running 'SMT OFF' at 1.41250V with LLC Level 5 at 4.5GHz and during Cinebench R23 testing, I noticed it doesn't go in the 80's (into the high 70's it does) in temperature on a 360AIO. Idle temps are in high 40's.
To me, this seems awesome since the 3900x boosts only a few of single cores to 4.6GHz at like a 1.5V burst or something, so theoretically I am ~0.1V lower to 4.5GHz all-core.

Only thing I can't remember if it's the voltage that will cause degradation or the temperature at which the voltage is set to being way too high (which in this case it isn't all that bad).
Is this worth having? 12c/12t @ 4.5GHz all with 1.41250 LLC-5, SMT OFF?

Also, a question: Does SMT enable 12 more "virtual" threads? Is that what hyperthreading is?
wont do more than 1.4v for that cpu even if its under 80s, Also if you are more to single core performance then yes disabling SMT might help, but if you want to make more use of the threads then it should be enabled.
 
'hyperthreading' is Intel's name for SMT...

(Although a handful of folks touted benefits during some games when disabling SMT during the first iteration of Threadripper, I've not heard it advocated for in several years, and, doubt it would gain you any benefits.)
 

Oxicoi

Honorable
Feb 7, 2017
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wont do more than 1.4v for that cpu even if its under 80s, Also if you are more to single core performance then yes disabling SMT might help, but if you want to make more use of the threads then it should be enabled.
I thought it would help in gaining a stable OC close enough to the max 4.6GHz that 3900x is known to go for with single core, instead putting it on all-core (only able to achieve 4.5GHz).

I would never be able to pass 4.3GHz all-core with SMT on, it was stuck on that. Is it even worth disabling 12 extra SMT threads for 200MHz more? I sort of just thought of that just now, lol.

'hyperthreading' is Intel's name for SMT...

(Although a handful of folks touted benefits during some games when disabling SMT during the first iteration of Threadripper, I've not heard it advocated for in several years, and, doubt it would gain you any benefits.)
Of course, I was just wondering if those threads were 'virtual' and not actual physical threads, hence the mention you made about some games benefiting since it uses real physical cores/threads. Is that the case though is what I'm concerned about.
 
I thought it would help in gaining a stable OC close enough to the max 4.6GHz that 3900x is known to go for with single core, instead putting it on all-core (only able to achieve 4.5GHz).

I would never be able to pass 4.3GHz all-core with SMT on, it was stuck on that. Is it even worth disabling 12 extra SMT threads for 200MHz more? I sort of just thought of that just now, lol.


Of course, I was just wondering if those threads were 'virtual' and not actual physical threads, hence the mention you made about some games benefiting since it uses real physical cores/threads. Is that the case though is what I'm concerned about.
Threads are "virtual by definition, you may want read up on it
Basically they are an improvement on old time multitasking on single core/thread CPU that use empty/idle clocks to do something else while waiting for input. In some ways they are also "real" as function is built in microcode
 

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