AM5/Zen4 is pretty limited

[Railgun]

More of a rant here than anything.

I’ve only ever built HEDT systems for the most part on both sides of the camp. And those I haven’t have been relatively bare-bones setups for the Mrs. So imagine my surprise when I’m looking to build a somewhat actual dedicated gaming platform only to find that what I actually want doesn’t exist.

Quick setup.

I‘ve recently acquired a 10-ish year old Nu-Gen arcade. Was their “elite” system back in the day, but quite old. Nothing wrong with it per-se, but figure I'm going to give this thing a massive shot in the arm. I've got an old 2080ti to recycle, and since I was going to build a new system, why not go new new. I started to convert the 2080 back to air, realized I'd mucked up all the old thermal pads then said screw it, I'll WC this thing.

I've got a 16TB "package" from Arcadesystems.co.uk, and also figure I will do some current PC games here. Only at 1080 resolution for the moment, so the 2080ti is more than enough. As I also want this thing to be as fast as possible, I did 4x 4TB NVMe SSDs, intending to leverage my Asus Hyper caddy, plus one for boot. Then it all went to pot (as they say out here).

Don't care about PCI-E 5, but didn't realize how limited the rest of the connectivity was on this platform. Opted for the ASRock X670E PG Lightning. The second x16 slot actually only being a x4 annoyed me. All the M.2 slots are inconsistent, some being only x2. The daisy chain of chipsets...what a cluster.

I really screwed myself by not researching, but for a new spec platform, it's crap. Utter crap. Why it's as limited as it is is beyond me. In the immediate term, I suppose it's "good enough," but man...

Will possibly end up with an AM4 platform, if that. May scrap AMD altogether depending on what I can actually find.

To add insult to injury, had a water leak while leak testing the GPU. Inlet block didn't seat correctly. I'd used older DI water I had which may have become less DI'd over time with some Mayhems X1. Dried the board extensively...and it's deader than a doornail. Not a single light or any other sign of life on the thing. Awaiting some IPA spray to ensure that no remaining residue is conductive, but I probably screwed the pooch here. First time that's ever happened like that.

 

[EarthDog]

Heh.. you'll be disappointed if you go intel...there are fewer lanes to go around there...also, am4 has less bandwidth/lanes than am5 iirc.

There are those that have a 2nd x16 slot that runs at 5.0 x8 (= 4.0 x16) and more consistent m.2 socket configs. Taichi Lite is a great example. 2x x16 slots (breaks down to x8/x8) four m.2 sockets... 3x 4.0 x4, 1x 5.0 x4.

Plenty of options out there... but budget boards won't do it.

 

[Railgun]

I have been looking for a x8/x8 as in the immediate term, won't matter as far as the GPU is concerned. Ideally, I'd like more consistent M.2 slots in terms of where they land (CPU vs chipset1 vs chipset2) but...to quote a Stones song.....

 

[EarthDog]

Ideally, I'd like more consistent M.2 slots in terms of where they land (CPU vs chipset1 vs chipset2)

Question...(outside of potential lane sharing, which is seen in the specs), why does that matter to an end user where it's connected? You can RAID across them, typically (again, depends on the board). Pcie 4/5.0 x4 is pcie 4/5.0 x4, right?

Get the right board for your needs is what this comes down to so far. Return that budget selection and get something appropriate for your desired configuration (which 4x nvme drives feels like awesome overkill, lol) There are plenty of options out there.

 

[mackerel]

The average consumer doesn't use that much connectivity. I do wish for a modern take on HEDT but it was a casualty of AMD starting the core wars.

Nearest to HEDT now would be Intel's current gen workstation offerings. It's essentially Alder Lake P cores on server based platform, and priced as such. AMD have yet to refresh Threadripper so the only alternative there is server level kit.

On consumer side I didn't think there was much difference in lane connectivity between Intel and AMD.
AMD AM5 CPU: 24 usable 5.0 lanes, chipset up to 12 4.0 lanes and 8 3.0 lanes.
Intel CPU gives: 16 5.0 lanes + 4 4.0 lanes, chipset up to 20 4.0 lanes and 8 3.0 lanes.

There's a lot of "up to" as the mobo maker could use those lanes for things before you get your hands on them.

 

[Railgun]

Question...(outside of potential lane sharing, which is seen in the specs), why does that matter to an end user where it's connected? You can RAID across them, typically (again, depends on the board). Pcie 4/5.0 x4 is pcie 4/5.0 x4, right?

Get the right board for your needs is what this comes down to so far. Return that budget selection and get something appropriate for your desired configuration (which 4x nvme drives feels like awesome overkill, lol) There are plenty of options out there.

Agreed. And it is only about lane sharing, and the stupidity that is my haste. As an "extreme" chipset, budget board or not, it's a massive misnomer. Why even have a x16 slot to begin with? They could have had open ended x4 and x2 slots to alleviate their marketing fluff. It's a poorly thought out and laid out design.

Just...why. Extreme my ***.



The specs are misleading. It doesn't support x4 mode, it can only operate in x4 mode. "Supports" to me reads bifurcation. That's not the case here. I usually don't go reading the manuals for the nitty gritty before buying.



As far as returning, after some water that's covered the board, which does work again after a dousing of isopropyl, I don't think it's returnable anymore. Yes, it was relatively inexpensive. Guess you get what you pay for.

The average consumer doesn't use that much connectivity. I do wish for a modern take on HEDT but it was a casualty of AMD starting the core wars.

Nearest to HEDT now would be Intel's current gen workstation offerings. It's essentially Alder Lake P cores on server based platform, and priced as such. AMD have yet to refresh Threadripper so the only alternative there is server level kit.

On consumer side I didn't think there was much difference in lane connectivity between Intel and AMD.
AMD AM5 CPU: 24 usable 5.0 lanes, chipset up to 12 4.0 lanes and 8 3.0 lanes.
Intel CPU gives: 16 5.0 lanes + 4 4.0 lanes, chipset up to 20 4.0 lanes and 8 3.0 lanes.

There's a lot of "up to" as the mobo maker could use those lanes for things before you get your hands on them.

The annoying thing is by forcing a spec that is largely irrelevant, they shoot themselves in the foot. Full whack NVMe BW is still a little ways out. By the time that and actually useful GPUs that would require that spec come out, the platform is at least 3 years old. Then what. X770E or whatever so you're buying a new platform anyway.

As it stands, there's more than enough bandwidth to leverage PCIE 4 and provide additional lanes. While the phy to the CPU may not have that many lanes, it should be trival to mux 40 PCIE 4 lanes into 20 PCIE 5. While there would probably be a marginal latency penalty, the average consumer wouldn't notice nor care. The power user would love the connectivity.

The short of it is, it's an expensive "high end" setup for not a lot of features. A massive contradiction. Shame that people just eat it up.

 

[EarthDog]

I hear ya.

The annoying thing is by forcing a spec that is largely irrelevant, they shoot themselves in the foot. Full whack NVMe BW is still a little ways out. By the time that and actually useful GPUs that would require that spec come out, the platform is 2-3 years old. Then what. X770E or whatever so you're buying a new platform anyway.

It's a chicken or the egg thing... kind of hard to have adaptation without there being something to work with it in the first place. 5.0 slots and 5.0 M.2 sockets have been around but only now have 5.0 M.2 drives come out. VIdeo card bandwidth still loses like 1-2% at 4.0 x8 (4090) so, the PCIe slot needs now (considering 4.0 x8 is like 1-2% difference) are seemingly ok for years to come. I don't think anyone 3-4 years from now buying a new video card will care about 4.0 x16 with 5.0 prevalent/standard/mature (didn't 7.0 get ratified already, lol).

While there would probably be a marginal latency penalty, the average consumer wouldn't notice nor care.

I was thinking the same on the lanes and how they are broken up, honestly. So few users run into issues, they don't care how it's broken up. You've been crossed by a 1% config (x16 RAID card) and a board that wasn't up to the task. You're not alone in missing the crossover platform that has more connectivity and flexibility (that also came at a price premium).

 

[Woomack]

A lot depends on the motherboard manufacturers. They design some pretty stupid motherboards and waste PCIe lanes or simply don't use as many as they can. Gigabyte had the best layout in the last gen (at least for me, but somehow they changed it. I mean, you could use a 5x M.2 PCIE 4.0 SSD and still run a graphics card at x16 and one more card at x4.
From AMD, better are some B650E than X670E. Check ASUS Strix B650E-E. It has PCIE 8+4+4 (or 16+4) and 4x M.2 PCIe: 2x M.2 PCIe 4.0 and 2x M.2 PCIe 5.0. It's one of the few mobos with 2x M.2 PCIe 5.0 on the market.
Most fast PCIe lanes are from the CPU, but not all are in use on most motherboards, and this is sometimes weird. On the other hand, Intel looks even worse, and storage is more limited.

Another thing is that current popular chipsets are not HEDT. HEDT in the form we remember from early Threadrippers and X series Intel died some time ago. Currently, you can pick highly overpriced Threadrippers and workstation Xeons. I used to buy Threadripper or X-Intel for about as much as right now a mid-shelf Ryzen/i7. I'm not even looking at new Threadrippers/Xeons as I can't spend yearly income on a PC.

Intel 700 and AMD 600 series chipsets are for the masses. Most, read like 95%+, users don't use anything else than a single graphics card and 1-2 M.2 SSD. If we look at the needs of most users, current options are still much better than most people will ever use.

Bifurcation is not supported by most motherboards. I mean, it could be, but there is no option in BIOS. Sometimes it appears on late BIOS releases, sometimes never. I needed it for x16 RAID cards, and only some motherboards were supporting it. You can also find even more misleading specs when some ASUS mobos with add-in cards have no info that when you use the card, then the graphics card slot will run at x4 or 1-2 M.2 sockets will be disabled. I had that in B550 mobo. In time you learn how to read the minds of people who write all these specs and expect problems that shouldn't be there.

 

[Archer0915]

Everything has limitations. I would say look at where you want to be and see how you can get there.

There is little performance difference between x8 and x16. In most cases you will see none. I run my video at 8, my other x16 slot runs at 4 so I can max out my SATA.

 

[Niku-Sama]

the lane sharing is why i went with the taichi b650e

the 16x slot wont kick down if you jam something else in the other 16x8 slot, its run off the chipset and not piped directly into the CPU like the top 16x. sure its not as fast but i dont think i'll need an expansion other than the gpu to be gen 5 16x piped directly to the cpu

 

[mackerel]

Bifurcation is quite widely supported, but the problem is more the lack of lanes meaning you don't get very useful splits out of it where it does exist. I used the link link below to figure out what possible configurations my generic 4x M.2 to x16 card might do.

[Motherboard] Compatibility of PCIE bifurcation between Hyper M.2 series Cards and Add-On Graphic Cards | Official Support | ASUS Global

As for multiplexing in its various forms, last I heard those chips were reportedly expensive, and their use is avoided where possible.

 

[freeagent]

Bifurcation is quite widely supported, but the problem is more the lack of lanes meaning you don't get very useful splits out of it where it does exist. I used the link link below to figure out what possible configurations my generic 4x M.2 to x16 card might do.

[Motherboard] Compatibility of PCIE bifurcation between Hyper M.2 series Cards and Add-On Graphic Cards | Official Support | ASUS Global

As for multiplexing in its various forms, last I heard those chips were reportedly expensive, and their use is avoided where possible.

Thanks for posting that link, I was using my card wrong.. I could only get it to see two, and not three because I had the ssd positioned wrong.. whoops.