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Comment by jacquesm | Hacker News Reader

I Picked a threadripper for a box that needed a lot of IO and figured that with that many PCI lanes I couldn't go wrong. But I have to admit I've been more than pleasantly surprised by the performance of the CPU as well, it - easily - outperforms all of the XEON and I7 based boxes that I have. The only thing I wished I would have done different is to max it out with 256G DIMMs when they weren't the price of a car.

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Zen 5 really is nice. I swapped my RAM from a Xeon W Sapphire Rapids machine into a Threadripper Pro 9000 series machine and I get almost double the memory read performance, plus it's a heck of a lot faster in single and multi core performance, and it runs cooler and quieter. Huge win all around. Aside from the price... (I went from Xeon W5-3435X to TR Pro 9985WX, eep.)

I have the complete opposite experience. Got a 9550x with 64gb ddr5 and a fairly high end mobo about two year ago. Just running the memory at stock speed. About 50% of the time I’d reboot and one or both of the sticks would only be detected as 2gb. Would need to do a hard shutdown to get it back.

I eventually gave up and turned off memory context restore and now I just deal with the minute plus (!) time to Post.

Not sure if amd memory controllers are just garbo or what but I’m going back to intel next chance I get.

What brand of ram, and was the ram listed on the supported spec sheet for the motherboard?

Up to date on bios updates?

Yes and yes, it’s crucial ram. Nothing exotic.

Weird, just had to check.

DDR5 has been kind of a mess imo, just in general.

Yea I’ve done endless googling around the issue and it seems to be a not uncommon issue with ddr5 but there’s no way I’m buying new parts now so I’ve come to peace with it.

Doesn't mean it can be broken. Also might be a CPU contact issue.

On the desktop Intel has better memory controllers last time I looked, but it’s not that big a difference. Something in your setup is just broken. Failures will happen with any brand, so I wouldn’t chalk it up to AMD vs Intel… figure out where your problem is and get the faulty part replaced if you can.

I feel you though, regardless of the cause, that is an extremely frustrating place to be.

Yea I’m just bummed because it’s a real expensive time to be swapping memory parts around. Like I said, things seem to just work without memory context restore so I’m fine with just paying the cost when I reboot once a week or whatever. I feel like the fact that disabling MCR fixes it should narrow down the issue to some part, I’m just not sure which.

> it’s a real expensive time to be swapping memory parts around.

It is, but isn’t it all warranty in your scenario?

It would be painful to claim though, as what part is at fault?

That's the problem, I have no idea. The fact that disabling MCR fixes it should point to something, but I'm not knowledgeable enough to know what.

> It is, but isn’t it all warranty in your scenario?

There are numerous recent stories of companies refusing to make good on their warranties and instead offering customers a refund for the original price paid. One example: https://www.tomshardware.com/pc-components/hdds/toshiba-refu...

For what it's worth, I have server with 128GB of DDR4 running 24/7 on cheapo AM4 consumer board. No issues whatsoever.

Did you set it to do memory training on every boot? That's a big stability help. Should also run Memtest86+ a few times. With some stick swapping you can determine if you have a bad stick or slot.

I went the opposite way and went back to Intel after many many years on AMD. I snagged a Xeon 654 Granite Rapids ($850) for a new workstation geared towards local inference. I don’t need a ton of CPU cores and all Granite Rapids have 8 memory channels where as you need very high end Threadrippers (9975wx for $4000) for an equivalent due to their CCD design.

As a bonus Granite Rapids is super power efficient and runs much cooler than my previous TR and Ryzens. Intel seems to be doing good things again! My only minor complaint is that P2P doesn’t work on my multiple GPU setup because every PCIe5x16 lane has its own dedicated root to the CPU, but all that bandwidth is useful for MoE models that are offloaded to RAM.

You could get a PCIe switch backplane, stick your GPUs on there and then have them communicate locally through the switch using p2p. For some GPUs you may have to use a hacked driver (google p2p 3090 for instance).

I wanted to do that, but didn't like any of the PCIe switches / backplanes I found (mostly due to price). Now, it might be worth buying one of these instead of trying to build a fancy PC. https://c-payne.com/products/pcie-gen4-switch-5x-x16-microch...

C-Payne makes excellent stuff but it is very pricey and supply is more than a little spotty, I've used pretty much all of his stuff by now and I am a very satisfied customer if I can order what I need, which more often than not is not the case.

A good alternative is ADT, they make excellent boards, there is a 4 and a 5 slot PCIe expander with a 88096 on it that works extremely well. I have two of these connected to my rig with their own power supply and four GPUs in each (and another two in the main machine). It's not exactly a portable affair (to put it mildly). Note that these won't work in a standard PC case due to the slot spacing so you'll have to rig something for that yourself (I use 2020 + some custom 3D printed fixtures).

Yeah, I had to go high-end to get one with enough CCDs to make use of the memory channels. I'm curious to know what all-read bandwidth you see when you run intel mlc on your system. My Xeon W5 was doing ~180GB/s after a lot of tuning, which was very disappointing. The Threadripper does ~320GB/s. From what I've heard, Granite Rapids is supposed to have solved the bandwidth problems that ailed Sapphire Rapids, so your numbers ought to be similar.

Threadripper is underrated for IO-heavy boxes. I made the same mistake with RAM prices, though; should have maxed it out when it was cheap

Ye, that's like saying one should've bought Amazon, Apple and Google stock when it was low.

That is only true if you only look at the market value of an asset.

One is a tool, the other is a speculative financial asset.

That's why I'm all in on hammers. Garage full of them.

Different kinds too? You never know when you might need a ball peen hammer or a soft faced hammer or a rubber or deadblow mallet or a framing hatchet. Why take the chance?

They bought the ram they needed when they needed it, and probably some extra too. Buying more than necessary is inherently a speculative action - you are betting on needing it in the future, and you are betting that it will be more expensive in the future. If it maintains its price it doesn't matter if you buy it now or later, if it gets cheaper or gets superseded by better alternatives then buying early is essentially a loss.

So in my view, this situation is almost exactly analogous to stock market speculation.

Hindsight remains 20/20, though.

In the computer world, wait a few years and things get cheaper. That was broken by an exceptional event. Who would have thought you can't afford DDR4 in 2026?

The upcoming shortage was public knowledge before the prices rose.

Just like an investment though - you need to have the money to play. I wasn't buying a computer at the time because [snip a long list of other toys I bought instead].

My current plan is to stick with my existing computers for a couple more years and hope this blows over. Time will tell.

We seem to be going back to the days when desktop PCs had a little lock hole.

They (in theory) could padlock them so the drives and ram couldn't be stolen?

https://francisuniverse.wordpress.com/2017/10/07/the-turbo-b...

I'm aiming for my machines to be too heavy and hard to open ;)

I put 256G in it wondering if I would ever need that much RAM and now it looks way too small. Highly frustrating. I wonder if the companies that made these deals realize that they've just given an entire industry a reason to look for alternatives. It's not like they wouldn't have sold their product otherwise.

I’ve been running the 64 core (128 logical cores) Threadripper PRO 3995WX in my dev machine for 4 years now (with 256gb ram).

Not sure I’ll need to upgrade my computer ever again :D

I picked up a pre-ai-price-insanity AX162-R at Hetzner a while back and loaded it up on memory to max out the 12 channels the 48c EPYC 9454P as a "this will be the last mysql box I'll need" and have I been _wildly_ impressed with it's performance. The things I throw at it are honestly laughable at times, wildly irresponsible queries against a rather large database, the redis qps metrics are ridiculous and I just load it up with random ggufs since the memory bandwidth is... not terrible and 384GB of it is... useful.

The web app that's hosted on it deals with lots of images and text - over 100mil of each deduplicated, embedded, simhashed - it does the hashing, and the embedding in real time during ingest. Just handles it.

These things are absolutely insane.

i have 2 epyc boards from 2019 and they are still just printing money

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