Okay, hear me out.

Currently, pretty much every PC in the world only has one kind of RAM (not counting CPU caches) – which is pretty much always just the single fastest RAM the builder could afford or needed. And then, if the computer needs more RAM than that, your only real option is to use swap space – to use space on hard drives or SSDs to store RAM data.

But swap space sucks because even with good SSDs, it’s way slower than RAM. You can easily have a lot of it, but it’s very very slow.

But what if motherboards were made to fit multiple types or RAM? You’d have your typical DDR5 for the main system RAM that gets used all the time, of course. But if that starts getting too full, instead of resorting to swap space, you instead have another tier of RAM in another set of slots, farther from the CPU – say, DDR3. Slower RAM than the primary DDR5, but still much faster than using swap space on a disk drive. And because it’s an old, cheap RAM standard, you can easily afford to buy and install a lot of it. (You could still have swap space as an additional buffer just in case your second tier of RAM also fills up, of course.) And when not needed for program and OS data, the 2nd tier RAM would be great for disk caching for commonly needed files…

You could, say, install 8GB of DDR5 alongside 64GB of DDR3. Most of your day-to-day stuff would be handled by the very fast DDR5 RAM, but when you’re doing something really RAM-intensive, you’d start to use the DDR3 as well. That would make your system slow down a bit, but not slow down nearly as much as if you were depending on swap space – it would still have a pretty acceptable level of performance, even when using the ‘swap’ RAM. Compared to a system with 16GB of DDR5, it would be equal when using 0-8GB of RAM, a bit slower when using 8-16GB of RAM, and much faster when using over 16GB of RAM. (And if the OS is intelligent about prioritizing fast RAM access for priority processes, you’d likely notice very little difference at all!)

And the time is ripe for this! With the RAM crisis we’re in now, it’s absurd to tell people “just buy more DDR5 instead”. If ever there was a time to implement multi-tiered RAM solutions, this would be it!

Of course, besides motherboard and CPU support, it will also need support on the software side. The operating system needs to know what to do with a second tier of slower RAM. But I’m sure that with a bit of cleverness in the engineering of it, you could make old, incompatible software at worst simply ignore the 2nd tier RAM as if it isn’t there at all, so even operating systems that don’t support this multi-tiered RAM could still run on the system, even if they don’t take full advantage of it.

I dunno … just a thought. Looking at the absurdity of using SSDs for temporary RAM-like storage when older-style RAM chips could provide faster and cheaper temporary storage … and probably more efficiently, too, since that’s their primary intended function. There’s no fundamental reason it couldn’t work, and it seems like a great compromise.

Or, for a solution that doesn’t require as much cooperation between MB manufacturers and OS developers, think of a PCIe card that has a bunch of DDR3 slots and presents itself to the MB/OS as a very fast SSD. A ‘ram disk’ that you then tell your OS to treat as swap space, so you’re then using it as RAM again. That approach might be a little slower with the PCIe bottleneck, but it would be compatible with almost any system and doesn’t require both a new MB and new OS.

(Though that approach could break ‘hibernate’ functions in cases where the OS uses allocated swap space to store RAM data for hibernation. The OS would expect that data to still be there after rebooting, but because it’s actually stored on RAM, the data would go away on power loss, breaking the hibernation function.)