Bro if you don’t have any clue about the answer, just don’t answer.
90GB is an absurd number for two reasons:
That’s significantly more RAM than any car has
RAM capacity is in powers of 2, which 90 isn’t. You could do 128GB, which is an even more absurd amount, or 64, which could be reasonable for a crazy infotainment system.
Don’t trust AI to give you answers if you don’t know how to tell when it lies to you.
It used to be all powers of 2, but kinda starting around DDR5 they started appearing in a sort of “sub power of 2”, so it’ll be two different powers of 2 added together - typically one step away from each other. So you’ll get like 16+8 (24) or 32+16 (48) or 64+32 (96)
Counter point to the mismatched modules point (I’m currently running 24GB in my own rig, so I did think of that possibility): I am pretty confident that there aren’t any cars running around with 5 ram slots. You could just sum the two 4 sticks to one 8 stick and throw it in a common dual channel four slot board, but then you’re mixing capacities on each channel, which either causes issues or just doesn’t work (it’s been a minute since I’ve done it). Also, from a manufacturing standpoint, having to install/manage four completely different items doesn’t scale as easily as just having one. In the volume that they’re buying, I’d bet that the cost savings from using smaller sticks would be pretty minimized by the extra cost/complexity of setting up processes for multiple items.
I’m going to look into the weird DIMM sizes that you mentioned. I’ve never seen them, so it might just be a gap in knowledge on my part.
IIRC, SDR -> DDR4 were a single 64bit wide data bus to the DIMM, but with DDR5 that was changed to a 2x 32bit data bus, thus allowing 2x 32bit reads to the DIMM to done independently. Due to the change to 32bit wide channels we can now have non power of 2 sizing of the actual memory chip itself… (basically the addressing modes changed to allow this).
In a car they are only putting in what thay need. The ram is soldered in so it can’t fall off when you hit a bump - that or complex/expensive fasteners.
Bro if you don’t have any clue about the answer, just don’t answer.
90GB is an absurd number for two reasons:
Don’t trust AI to give you answers if you don’t know how to tell when it lies to you.
Individual modules may usually be powers of two, but a machine can make use of multiple mismatched modules. 64+16+4+4+2=90
I do still think that AI overview answer is bogus, but it’s not impossible.
EDIT: Now that I think of it, I have definitely seen individual consumer DIMMs in 24, 48, or 96 GB. So, not always just powers of two.
It used to be all powers of 2, but kinda starting around DDR5 they started appearing in a sort of “sub power of 2”, so it’ll be two different powers of 2 added together - typically one step away from each other. So you’ll get like 16+8 (24) or 32+16 (48) or 64+32 (96)
Both very good points.
Counter point to the mismatched modules point (I’m currently running 24GB in my own rig, so I did think of that possibility): I am pretty confident that there aren’t any cars running around with 5 ram slots. You could just sum the two 4 sticks to one 8 stick and throw it in a common dual channel four slot board, but then you’re mixing capacities on each channel, which either causes issues or just doesn’t work (it’s been a minute since I’ve done it). Also, from a manufacturing standpoint, having to install/manage four completely different items doesn’t scale as easily as just having one. In the volume that they’re buying, I’d bet that the cost savings from using smaller sticks would be pretty minimized by the extra cost/complexity of setting up processes for multiple items.
I’m going to look into the weird DIMM sizes that you mentioned. I’ve never seen them, so it might just be a gap in knowledge on my part.
I found this comment:
And that seems to be backed up under “subchannels” on the ddr5 Wikipedia page.
Neato, thanks for teaching me something new
In a car they are only putting in what thay need. The ram is soldered in so it can’t fall off when you hit a bump - that or complex/expensive fasteners.