AMD and Intel differ so much in their approach to CPU design that trying to compare Ryzen Gen 3 to Intel Coffee Lake Gen 10 is a chalk and cheese endeavour.
While both want to dominate the x86 world, AMD and Intel are significantly different in concept and design – but there is room for both.
The critical difference that separates AMD and Intel processors today is that AMD uses a chiplet design, while Intel uses a monolithic approach.
But what do these terms even mean? And what do the differences between AMD and Intel really mean for you as a customer?
Gamer, author and part-time Gadgeteer Arjun Lal writes:
AMD and Intel do the same but very differently – Let’s take a deep dive
Intel’s Monolithic Approach: Big, single and increasing thinner (nm) chips
In Intel’s monolithic approach, everything about a processor – all its cores, cache, graphics, and I/O – is on a single die. With smaller processor designs–between 2-4 cores this is easy to do. Each die is relatively tiny, and you fit lots onto silicon wafers – leading to a relatively lower cost to manufacture a complete system on a chip.
Even if defect rates (yield) were to increase, wastage levels are low enough that Intel’s marginal cost of production isn’t hit. Every chip Intel builds–from dual-core Celerons right up to 28-core Xeon behemoths has its own die and design.
To be fair to Intel, it will move to a hybrid chiplet design if only to offer more options. In the example below it could use the same monolithic CPU core die and add custom I/O, Comms (e.g. 5G) and more making it a very flexible chip.
AMD’s Approach: Multiple, discrete chiplets build the chip
AMD’s chiplet design is the opposite. The fundamental unit of every Ryzen processor is the CCX, a four-core/eight-thread set of CPU cores. The CCX is a quad-core processor. Two CCXs pack together with L3 cache and I/O on a separate die to form a CCD.
And up to seven CCDs can stack together in a Ryzen Multi-Chip-Module (MCM). CCXs in a CCD communicate with each other, and other CCXs via the Infinity Fabric interconnect. Infinity Fabric binds the CCXs to the cache, I/O and interconnects different CCDs.
Monolithic vs Chiplet: What are the implications?
First, Intel’s per-unit production cost is lower with smaller processor designs. A dual-core Celeron or Pentium sits on a small low cost, high-yield die.
Secondly, Intel’s performance across cores is better due to a physics: a monolithic die has less of latency than connected chiplets.
While Infinity Fabric is very fast, there’s still a latency penalty as the CCDs are physically separated. Electrons can only travel so fast, according to Galileo.
With Ryzen Gen 1 and 2, the latency penalty had a noticeable performance impact, especially in games. However, AMD has significantly increased cache size up to 72 MB for the Ryzen 3900X. This, together with intelligent scheduling buffers tasks so that latency isn’t a big deal.
Why Ryzen’s hard to beat on price
Linear and Exponential Price scaling does it every time!