> Yes, DDR3 is the lowest CAS latency and lasts ALOT longer.

DDR5 is more reliable. Where are you getting this info that DDR3 lasts longer?

DDR5 runs at lower voltages, uses modern processes, and has on-die ECC.

This is already showing up in reduced failure rates for DDR5 fleets: https://ieeexplore.ieee.org/document/11068349

The other comment already covered why comparing CAS latency is misleading. CAS latency is measured in clock cycles. Multiply by the length of a clock cycle to get the CAS delay.

CAS latency is specified in cycles and clock rates are increasing, so despite the number getting bigger there's actually been a small improvement in latency with each generation.

Old machines use a lot more power (worse nm), and DDR5 has equivalent to ECC, while previously you had to specifically get ECC RAM and it wouldn't work on cheaper Intel hardware (bulk of old hardware is going to be Intel).

> 100.000 writes per bit

per cell*

Also, that SSD example is wildly untrue. Especially with the context of available capacity at the time. You CAN get modern SSD's with mind boggling write endurance per cell, AND has multides more cells, resulting in vastly more durable media than what was available pre 2015. The one caveat there to modern stuff being better than older stuff is Optane (the enterprise stuff like the 905P or P5800X, not that memory and SSD combo shitshow that Intel was shoveling out the consumer door). We still haven't reached parity with the 3DXpoint stuff, and it's a damn shame Intel hurt itself in it's confusion and cancelled that, because boy would they and Micron be printing money hand over fist right now if they were still making them. Still, Point being: Not everything is a TLC/QLC 0.3DWPD disposable drive like has become standard in the consumer space. If you want write endurance, capacity, and/or performance, you have more and better options today than ever before (Optane/3DXPoint excepted).

Regarding CPU's, they still follow that durability pattern if you unfuck what Intel and AMD are doing with boosting behavior and limit them to perform with the margins that they used to "back in the day". This is more of a problem on the consumer side (Core/Ryzen) than the enterprise side (Epyc/Xeon). It's also part of why the OC market is dying (save for maybe the XOC market that is having fun with LN2), those CPU's (especially consumer ones) come from the factory with much less margin for pushing things, because they're already close to their limit without exceedingly robust cooling.

I have no idea what the relative durability of RAM is tbh, it's been pretty bulletproof in my experience over the years, or at least bulletproof enough for my usecases that I haven't really noticed a difference. Notable exception is what I see in GPU's, but that is largely heat-death related and often a result of poor QA by the AIB that made it (eg, thermal pads not making contact with the GDDR modules).

CAS latency doesn't matter so much as ns of total random-access latency and the raw clockspeed of the individual RAM cells. If you are accessing the same cell repeatedly, RAM hasn't gotten faster in years (around DDR2 IIRC).