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$2800 is still a huge price in comparison with the last year.

Last summer, a 9950X3D + motherboard + cooler + 128 GB DRAM + VAT sales taxes was the equivalent of $1400 in Europe, where I live.

That's half of your quoted price. That was without case and PSU, but adding e.g. $200 for those would not change much.

In January I upgraded my desktop, 9950X3D £600, 64GB DDR5-6000 £600, MSI MAG Tomahawk X870E £300, Samsung 990 Pro 4TB £350, Asus Prime 9070XT £580. I spent a another £250 on PSU and cooler and reused my case (Phanteks Evolv Enthoo TG, beautiful case but horrible cooling. Will cut some holes in it and if it doesnt work out look for something with more airflow).

The RAM price was already inflated at that time, and the same kit is now £800, but in October or earlier last year I'd have saved possibly the cost of the CPU/GPU on the whole thing, but now it's be about the cost of a CPU/GPU more expensive.

On a side note for anyone not aware, 9950X3D isn't the best choice for pure gaming, 9850X3D is cheaper and marginally better, also I went with 2 sticks of RAM kit, 4 sticks is much harder to run at the advertised speed (6000) which is actually an overclock.

Im a dev and a linux user/gamer hence my choice of CPU/GPU.

Very similar config, but I bought a second pair of ram. Running 4 sticks at 3600. Also, the LAN port of the motherboard stopped working after a week, so I had to buy an Ethernet card

Ouch, were you not willing to RMA for that ethernet port? I wouldn't be too pleased after only a week if parts of the board stopped working.

I don't really want to run my RAM that slow which is why I'll probably stick with two sticks.

Yes of course. We all know prices are up.

I commented because someone thought that $4K was the going price for 128GB of RAM, which is way too much even with the demand crunch.

Due to the high prices of DRAM and SSDs they now are the greatest fractions of the total price of a computer.

In January I was forced to upgrade an ancient Intel NUC, by replacing it with an Arrow Lake H based ASUS NUC. The complete system with 32 GB DRAM and 3 TB SSDs has cost EUR 1200, including VAT sales tax.

The distribution of the price was like this:

  Barebone mini-PC:   41%
  32 GB DDR5 SODIMMs: 26%
  2 TB PCIe 5.0 SSD:  24%
  1 TB PCIe 4.0 SSD:   9%

Since then, the prices of DDR5 and SSDs have continued to increase, so now the fraction spent for memory would be even higher than 59%.

Before 2026, for so small amounts of memory its cost would have been much less than the rest of the system.

I bought 192GB (4x 48GB) of DDR5-6400 for 299 euro in September but returned it because I couldn't get 4 DIMMS to run at decent speeds in the system.

6 or so weeks after I returned it the kit was listed at 1499.

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

Got it running with 4800MT/s and literally 30 minute boot times in an AM5 machine. The 30 minute boot time could be worked around by enabling the (off-by-default) memory context restore option in BIOS, but it really made me think something was broken and it wasn't until I found other people talking about 30 minute boot times that I stopped debugging and just let it sit for an eternity.

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.

I’m in the same situation! My machine will take 2-5 minute to post every few reboots, it seems random. The messed up part is the marketing material says this things can handle 256gb of ram or whatever absurd number, f me for thinking then 128gb should be no problem. Honestly this whole thing has soured me on AMD. Yea they have bigger numbers than intel but at what cost, stability?

Check you have MCR (Memory Context Restore) enabled, otherwise you train the RAM way more often than you need to (every boot).

Your machine takes 30 minutes to boot because of the RAM? Or it takes 30 minutes to load a model?

It's the RAM. It needs to "trained" which takes some time but for for some reason these boards seem to randomly forget their training, requiring it to happen again.

I've never had memory training be forgotten with my AM4 nor LPDDR5-based laptops and NUCs. Is this a new thing with AM5 or something? Or just a certain brand of BIOSes?

It's a common issue on consumer boards with DDR5 and more than two DIMMs installed.

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.

Ok, so user selects too-high speed, controller tries for ages and fails, but doesn't save since it's overridden by user in BIOS?

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.

Wonder if DDR5 ECC ram has the same problem? I'm meaning the real ECC stuff, not the "on chip only ECC" that all DDR5 has.

The controllers which support ECC are usually a lot better and able to handle more channels. They also typically require active cooling.

Interesting. Didn't know about the active cooling requirement.

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.

huh, its been a decade since i built a PC, whats changed?

DDR5 is much, much more fickle than DDR4 and earlier standards. I think it's primarily due to pushing clock speeds (6000 MT/s would be insanely fast for DDR4, but kinda slow for DDR5).

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.

My guess is bigger numbers, higher voltages, tighter timings.

It's an AMD thing

You need to enable MCR (which trains the memory once and caches the result for (iirc) 30 days) otherwise yeah, booting is horribly slow, even the 64GB I have can take several minutes but with MCR it boots basically instantly.

Some motherboards have it off by default.

Memory training seems to be getting faster with each bios update. In 2024 when I upgraded to AM5, 64GB memory training took like 15 minutes. Now the same setup takes about a minute when it needs to retrain, then near instant with MCR (Windows 11 takes significantly longer to load than the POST process).

From my comment:

> The 30 minute boot time could be worked around by enabling the (off-by-default) memory context restore option in BIOS

I’m running 128gb on a 9550x now with 4x32gb sticks and it’s terrible. It’s unstsable, post time is about 2 minutes (not exaggerating)and I’m stuck at a lower speed. I’m considering just taking 2 of the sticks out and working with 64gb and increasing my swap partition. The nvme drive is fast at least.

This is my first time off intel and I have to say I don’t understand the hype.

> It’s unstsable, post time is about 2 minutes (not exaggerating)

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.

What ddr5 speed are you running? 6000 is technically an over clock, AMD only guarantees being able to run at something like 4800 or 5200.

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

I just yanked two of the sticks out. Who knows, maybe I'll sell them. 64gb is sufficient most of the time anyway, and now I'm running at 4800 instead of 3600 and the boot is much faster. Thanks AMD!

Threadripper is a good alternative. No point having a lot of dual channel ram for LLMs, too slow

I had the same issue with Intel. It's not guaranteed there either.

No such bundle deals where I am. Absolute cheapest DDR5 128GB kit around is 2 sticks of 5600 64GB for $2k.

Cheapest 64GB kit is $930.

The kit I was oh-so-close to buying was two 6400 64GB sticks.

Not gonna buy now, not that desperate. I have a spare AM4 board, DDR4 memory and heck even CPU, I'll ride this one out. Likely skip AM5 entirely if something doesn't drastically change.

> Absolute cheapest DDR5 128GB kit around is 2 sticks of 5600 64GB for $2k.

That's not far from the bundle deal above, once you subtract the $700 CPU.

If you really need 128GB the 5600 kit is fine. Having 208MB of total cache on the CPU means the real world difference between a 5600 kit and a slightly faster kit is negligible in most use cases.

If you don't need to upgrade then clearly don't force an upgrade right now. I just wanted to comment that $4K for 128GB of RAM is a very bad price right now, even with the current situation.

> a slightly faster kit is negligible in most use cases

Does that “most use cases” caveat really apply to someone buying 128G of RAM? If I’m buying that much, it means I’m actually going to put it through its paces, unless it’s just there for huge reserved guest VM overhead.

The 208MB of total cache on the CPU we’re discussing does a good job of reducing sensitivity to RAM speed differences on this platform.

If you’re trying to run LLMs off of the CPU instead of the GPU then the RAM speed dictates a lot. It’s going to be slow mo matter what, though. Dual channel DDR5 just isn’t enough to run large LLMs that start to fill 128GB of RAM and the difference between 5600 and 6400 isn’t going to make it usable.

If you’re just running a lot of VMs or doing a lot of mixed tasks that keep a lot of RAM occupied then you’d probably have a hard time measuring a difference between 5600 and 6400 if you tried with one of these X3D CPUs with a lot of cache.

This is a frequent topic of discussion for gamers because some people obsess over optimizing their RAM speed and timings and pay large premiums for RAM with CAS latency of 28 instead of 36. Then they see benchmarks showing 1-2% differences in games or even most productivity apps and realize they would have been better spending that extra money on the next faster GPU or CPU or other part.

> I just wanted to comment that $4K for 128GB of RAM is a very bad price right now

Oh absolutely. Just mentioned it since I was very close to buying it back then, and now it's completely bonkers.

That bundle deal is quite well priced all things considered, it basically prices the memory where it was. Again, sadly no great bundle deals here.

that bs of you don't need 128 are toxic. what if you want to upgrade from ddr4 and you already have 128?