It is curious that if we take a listing of specs from Intel and AMD of their desktop and server CPUs for the same structure and see the variations, we are going to understand two fairly fascinating elements: there’s a massive hole in frequencies and consumption. Why does this occur if the effectivity and the nodes are equal?
The game-changing elements: server vs desktop, frequencies and cores
There are many elements that make this so, so we’re going to attempt to break them down in a number of key factors and touch upon them, since as we properly know they are completely completely different product traces and though it could not look like it, Intel and AMD comply with completely different and really curious paths to this method.
Let’s begin at the backside, since EPYC vs Ryzen and Core vs Xeon are two unbiased fights which are conceived from the second zero to method the markets from the wafers. And right here is the first palpable distinction to put us: Intel has completely different fabs for Core and Xeon processors, whereas AMD orders every part from TSMC and they use the same wafers for EPYC and Ryzen.
Why is that this consultant? Well, as a result of as we all know, the server traces use the finest chips to have the least attainable energy leaks. And right here we hyperlink to the second consultant issue: power effectivity and its relationship with thermal density.
Again the query could be why? Well, due to the sort of use and hundreds that one and the different will bear. Server processors are standardized with sustained a great deal of 100% 24/7 utilization, which signifies that the CPU will devour all of its TDP all the time. Therefore, a extra environment friendly ASIC by way of energy leakage is a vital enchancment that may save electrical energy, voltage, consumption and due to this fact temperature.
The ratio of effectivity, frequency and cores
With this in thoughts it’s logical to suppose that the variety of cores must be the most that enables each the structure, chip, wafers and platform, as we search the highest efficiency per packaging. But then the frequencies are going to undergo from the scalability of voltage, effectivity and power.
And it’s that the cores as such will not be solely accountable for the enhance in the ratio of watts / core, however we additionally need to depend on the variety of buses and cache that embrace this class of processors. Buses are a big supply of wattage consumption, however they are wanted to extend for instance the variety of RAM channels or simply some like PCIe or USB.
Finally, we take note of the stability issue. A server CPU must be completely secure over time, since it would absolutely not relaxation till its mission ends a few years later, in some instances even a decade. Therefore, a server CPU will all the time search for the finest ratio of frequencies / core / consumption / temperature / stabilityTherefore, the finest solution to obtain it’s to decrease frequencies and voltage with out dropping the largest variety of cores of view for the platform for which they are supposed.