Which regular desktop tasks are kneecapped by 80GBps memory bandwidth?

If local LLMs become mainstream then you want as much memory bandwidth as possible. For regular home and office use two channels of DDR4 is more than enough.

You really start taking into account bandwidth when you need 64GB or more (which is rarelly).

If it's audio/video, spawning VMs, it doesn't matter much. If it's for generative software, it might become an issue.

Unironically, small LLMs

LLMs and fast GPUs without having a giant PC spring to mind.

It is not more than 60 Gb/s for extreme overclocked DDR4-4000 and sometimes much less than 50Gb/s for regular 3200 DDR5 is reaching 100 Gb/s overclocked for Intel, and 50-70 Gb/s in stock.

When factoring in motherboard, CPU etc, then yes. The max speed is only theoretical, unlike the Apple chips which actually benchmark on the speed specified.

That's such an Apple fanboy trope. The bandwidth is shared with the GPU part that actually uses most of it. You can't starve the CPUs for data in typical PC with the "standard" DDR5 bandwidth and they have much higher bandwidth for GPUs.

You know it's almost like if PC industry hardware designers are not complete morons.