> When you have CPU, GPU, and even DRAM sitting on the same "die
Apple has been really successful convincing people they've done something special here. Given how many people are so horribly misinformed about this I'd go so far as to call it false advertising.
No, the DRAM is not on the same die. It's on package. They're literally standard SK Hynix memory chips.
Yes technically there's a latency advantage, but comparing M1 to DDR5 desktop chips Apple actually has worse overall memory latency.
Every integrated graphics chip from Intel and AMD has had unified memory for the last 10+ years.
Compute itself is also not what makes the Apple chips get long battery life. Looking at tests under full load the M1 is significantly worse than the latest Intel or AMD, yet it still gets better battery life under normal usage. The efficiency does not come from compute but from a whole host of idle consumption optimisations Apple brought over from their phone chips.