Yeah the only way to run 4 sticks of DDR5 decently is with Intel. It's a bit of a shame that you can't cram enough RAM to run big models.
The most I could get running on 10GB VRAM + 96GB RAM was a REAP'd + quantized version of MiniMax-M2.5
The most I could get running on 10GB VRAM + 96GB RAM was a REAP'd + quantized version of MiniMax-M2.5
It's so bad. I don't get why they sell AM5 motherboards with 4 RAM slots.
At least that system has been running well for like two years. But had I known that the situation is so much more dire than with DDR4, I would've just gotten the same amount of RAM in two sticks rather than four.
Memory training has always been a thing: during boot, your PC runs tests to work out what slight changes between signals and stuff it needs to adapt to the specific requirements of your particular hardware. With DDR4 and earlier, that was really fast because the timings were so relatively loose. With DDR5, it can be really slow because the timings are so tight.
That's my best understanding of it at least.
Doesn’t affect soldered memory or lower speed memory (like DDR4). Many memory controllers fail to achieve good speeds and timings at all on 4 DDR5 DIMMs, and fall back to running DDR5 at 3600MHz instead.
That being said, it's not hard to get a hold of a reasonably modern DDR5 EPYC board. Something like this: https://www.phoronix.com/review/gigabyte-mz33-ar1
Expensive though.
I distinctly recall thinking my LPDDR5 NUCs were broken since they seemingly didn't boot the first time, until I recalled the training stuff. Took up to 15 minute on one of them. But neither has had any issues since, hence my question.
Some motherboards have it off by default.
> The 30 minute boot time could be worked around by enabling the (off-by-default) memory context restore option in BIOS
This is my first time off intel and I have to say I don’t understand the hype.
The long POST times must mean it's retraining the memory each time, which is not normal. Just in case you haven'ttried it yet, I'd start by reseating them, I've had weird issues with marginally seated RAM before.
Also you definitely have to go much slower with 4 sticks compared to two, so lower speed as much as you can. If that doesn't help, I'd verify them in pairs.
If they work in pairs but not in quad at the slowest speed, something is surely wrong.
Once you get them working in quad, you can start bumping up the speed, might need voltage boost as well.
You may need to bump up voltages slightly for your CPU's IMC (I needed to on my ryzen 8700F to run 6000 stable). Its CPU sample dependant.
Also as other commenter pointed out, typically 4 sticks will achieve lower stable clocks