HanakoLexie a écrit :
Max performance > PPT 500 pour pas être bride par lui, ensuite on max le TDC pour pas être bride par lui non plus, et on fini par trouve l'EDC qui va donné le meilleur score sur CBR15/20/23.
Maintenant quelque remarque, pas tous les CPU préfère un EDC réduit, par exemple sur un 5600X qui est à 88 PPT - 60 TDC - 90 EDC va plutôt avoir tendance à perf le mieux au alentour de EDC 110 a 130.
Un 5800X lui qui est donné pour 142 PPT - 90 TDC - 140 EDC va trouver son max performance en réduisant EDC dans les 80 a 115.
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Ce qu'est , (ou semble etre ?) EDC est à rebours de ce qui prévaut et se dit habituellement, cad une valeur 'burst' capable de convenir à (fournir) un peak d'amperage demandé . En fait il s'agirait plus d'une valeur transitoire "adhoc" certes mais ...de limitation (!) pour pas tout peter si on laissait la mobo envoyer une sauce "normale" d'amperes en rapport avec un gros peak ; à supposer qu'elle puisse effectivement envoyer une valeur tres anormale !? la question se pose puisque par ex sur une mobo Asus "PBO Enhancer" va désactiver cette limite EDC , ce 'controle' amperage tel que mentionné ...bref que penser de tout ça ?
en anglais cela donne :
6/10/21 - Clarification and more detail on EDC:
EDC (Electrical Design Current) is in place to keep the processor from requesting more power than the motherboard VRM's can handle. Most vendors have more than enough VRM headroom to handle absurd EDC values (but not insane ones like I talked about above). Although I believe I explained it well above, I am adding this just to explain it a different way.
EDC exists so that the processor does not suddenly ask for power levels exceeding the motherboards VRM design capacity (sudden load surge current). The reason WHY is because if a VRM where to catastrophically fail, you will either get an open circuit (so 0.0v) and you'll be out a motherboard, or worst case scenario, a dead short (12.0v) and you are down a processor and motherboard (or more). TDC current is what ACTUALLY flows through the silicon and TDC is what can, and will, kill your CPU if you get stupid with it. TDP, TDC and PPT/PPL are the 3 values that directly relate to keeping the processor safe, and those 3 values are all interrelated and mutually exclusive to EDC. EDC is surge current, but does not represent REAL power (actual RMS power/current). TDC is representative of your actual REAL power.
le passage sur ce que *devrait* fournir la mobo , et donc qualifié de "insane" est décrit comme suit :
There is an infinite amount of opinions out there on EDC, and a lack of facts from AMD. This is my understanding based on my electrical engineering and physics knowledge (which I am sure will be argued with). EDC outlines the base surge current the motherboard VRM’s have to handle in worst case scenarios, in this case a sudden 24 thread AVX load. For example, at full load 4.57Ghz boost in cinebench single thread, TDC current is 15 amps. For 24 threads that would be 360A and that is obviously out of the question. I very seriously doubt there are many motherboards on the market that could handle that much current, if any. A 12 volt 8-pin EPS connector is rated at 250 amps for example, but that doesn’t mean the VRM’s are. Even if they could, Ohm’s law makes it impossible because your processor would be drawing 540 watts at 1.5 volts. It would melt. Even at the other extreme, at 1.1 volts it would be drawing 394 watts which is also impossible because you would be unstable at 1.1v @ 4.57Ghz. The bottom line is, unless your CPU is a dead short zero ohms, it ain’t happening.
Message édité par kobaia le 28-12-2022 à 22:59:42