New system, AM4 or AM5?

[Dirk Broer]

When you want to build a new cruncher you are currently faced with the choice to go for the trusted, proven and cheaper AM4 platform vs the new, unproven and expensive AM5.
Or, when you have plenty of cash, you might consider a choice between the trusted, proven and expensive WRX40 platform vs the completely new, totally unproven and very expensive TR5.

Boy oh boy, what to choose? Remember we're only in it for the crunching, so RGB does not come into our considerations. We want solid performance, some overclock potential, steady VRMs and M.2 NVMe slots with PCI-e 4.0 x4 -at least. And plenty of fan headers, too.

So: out go the A520 and (most of the) A620 boards, as they offer 'only' M.2 NVMe slots with PCI-e 3.0 x4 -and sometimes even PCI-e 3.0 x2. The 'A' chipsets can't be overclocked either, and generally have lesser quality VRMs.

The 600 series of chipsets differ from the 500 (B550 and X570) series as they fall apart in four: B650, B650E, X570 and X570E.
The E or "Extreme" branding is a guarantee that PCIe 5.0 is supported on both the motherboard's graphics slot and NVMe slots. E models provide access to all 24 PCIe 5.0 lanes from the processor. Non-E models only support 8 PCIe 5.0 lanes on NVMe slots while the rest of the lanes on graphics slots are dropped to PCIe 4.0. That's nice to know, isn't it?

To be continued/upgraded....

[plonk420]

i'd almost lean towards AM5. CPUs are finally competitive in price. there's a mobo or two that's not stupid expensive if you don't care about slots or USB ports (B650 HDV/m.2 whatever good. A620 HDV/m.2 bad, tho). and probably can't be a *bad* thing to at least HAVE AVX512. and it's nice not to need a dGPU (or to have to mess with one if you're running headless and it suddenly decides to not fully boot into the OS). and then there's always ECO mode. give up a few percent in performance, gain looooots of efficiency ��

the only concern is DDR5, tho if you're not building a farm of them, it's not TOOOO bad. not as bad as the DDR4 shortage soon after its launch ��

and i'm hoping/looking forward to Hardware Unboxed reviewing more A620 boards!

[Dirk Broer]

i'd almost lean towards AM5.

Some points to think over in the case for AM4 -at the present moment.
Schermafbeelding 2023-05-05 114839.jpg
and support for my thoughts byChristopher Barnatt from explainingcomputers.com

[Dirk Broer]

AM5 on the cheap, one year later:

For a cheap cruncher we only need a Mobo, a CPU/APU, a M.2 SSD and some DDR5 (I prefer at least 4GB per thread, so at least 48GB in case of the six-core/12 thread CPUs that are the budget choice, while more is better).
We just re-use an existing case/PSU combination for the sake of money.

So an A620 board, preferably with four ram-slots and decent VRM-cooling. While (some) A620 boards may be limited to 65W Tdp CPUs, but so are budget (around 180 Euro's) AM5 CPUs, like:

• the AMD Ryzen 5 8500G (with IGP, Boxed),
• the AMD Ryzen 5 7500F (without IGP, Tray) and
• the AMD Ryzen 5 7600 (with minimal IGP, Boxed).

Below 100 Euro's/US Dollars no motherboard brand offers any VRM cooling, and the cheapest board that I like appears to be the ASRock A620M Pro RS, at some 117 Euro's, YMMV.
The WiFi version comes at 130 Euro's, but I get fiber (at 400Gb/s instead of 20Gb/s download now -upload is even 400Gb/s instead of 1Gb/s now) soon so: why bother with WiFi? I love Cat 7 cables.
ASUS fans might want the ASUS TUF Gaming A620-Pro WiFi, an ATX board at some 170 Euro's, but for that price you can actually already buy a decent B650 mobo, like the ASRock B650M Pro RS

48 GB Corsair Vengeance CMK48GX5M2E6000C36 comes at a little short of 165 Euro's

A WD Blue SN580 1TB may not be the fastest SSD your money can buy, at some 67 Euro it is the cheapest 1 TB PCIe 4.0 x4 drive you can buy, and it runs pretty cheap too: 0.065Watt for both reading and writing -a fast Samsung 990 Pro needs 5,4Watt to do so, almost 100 times as much.

Thus:
155 CPU (Ryzen 5 8500G)
111 Mobo ( ASRock A620M Pro RS)
165 RAM (48 GB Corsair Vengeance CMK48GX5M2E6000C36)
67 SSD
----+
498

and now consider that choice compared to the price of an AM4 Ryzen 9 5950X as an upgrade in your present AM4 system...

[vaughan]

I would go for the extra cache offered by an X3D style CPU

[Dirk Broer]

As Vaughan just gave another reason to prefer an upgrade of an existing AM4 system over a new AM5-based on an A620 chipset, let's dive a level deeper.

As you can only spend your money once, let's make it worthwhile. An existing AM4 system can be upgraded to take a new AM4 AMD Ryzen 9 or AMD Ryzen 7 X3D CPU, 32 to 64 GB additional DDR4 RAM and e.g. a new RTX 3500 (or better) at the price of a basic AM5 system based upon a A620 chipset. This is mainly because in the latter case you need to buy a new mobo too, and all your new DDR5 RAM.

But when money is no objection, AM5 is the way to go now, consumer system-wise!

The AMD Ryzen 9 7950X3D combines both Vaughan's and mine preferences: a huge X3D cache and 16 cores/32 threads for SRBase and PrimeGrid. This needs 128GB of DDR5 if you want 4GB per thread.
And if we want all the goodies of the AM5 platform, we need the B650E or preferably the X670E chipset boards to make use of PCIe 5.0 for both the GPU(s) and the M.2 SSDs.

If and when even 32 thread CPUs are not enough -e.g. in case you might want to crunch the 64- or 128-thread Yoyo WUs- there's the sTR5 platform for the latest Threadripppers (up to 64 cores/128threads) or the SP5 platform for the latest EPYCs (up to 128 cores/256 threads)

[Dirk Broer]

Everyone has his/her own user case to consider (gaming, crunching, economics, bling-bling, etc.), but here is some food for thought regarding the AM4 vs the AM5 platform:
Schermafbeelding 2024-05-25 013428.jpg (click unto to make bigger)

If you look in the money/threads column you see that the AM4 platform still has its advantages, but that is the one-time purchase moment.
The everyday economics might be better served with the AM5 Ryzen 9 7900 though, though the AM4 Ryzen 9 5950X is a good contender too.

When you need that big L3 cache and economics play a part too, you'd best buy a AM4 Ryzen 7 5700X3D -and search for articles to clock it down so it consumes a mere 65 Watt. And, when money is the least of your worries: you'd better buy a brand-new 64 core Threadripper.

[vaughan]

I went with 4 of the AM4 Ryzen 7 5700X3D but now regret I didn't go for the AM5 chip. The DDR5 RAM became a reasonable price.

[Dirk Broer]

I've decided to go for the Ryzen 9 5950X to replace my Ryzen 7 5700X in the MSI B550-A Pro system at 340 Euro
The Ryzen 7 5700X in its turn will replace my Ryzen 7 1700 in the ASRock AB350M Pro4, to make an upgrade to Windows 11 possible in that system.
I've also decided to buy a Ryzen 7 5700G to replace my Ryzen 5 2400G in the MSI B450 Tomahawk MAX II system at 160 Euro. This will also make an upgrade to Windows 11 possible on that system.

Both the Ryzen 7 1700 and the Ryzen 5 2400G will be running Linux soon, which isn't bound by artificial hardware boundaries -at least not to the extend Windows is.
Just have to score some AM4 mobo's for them....