B550 PCIe questions

Digital Viper-X-

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I currently have an 8700k with a Z370 board.
Currently running 2 NVME drives, 1 PCIe Wifi card + my GPU, the GPU is forced down to 8x with this setup. Would a B550 allow me to run 16x on the gpu? also does it support PCIe 4.0 for the GPU since it comes directly from the CPU?

Thanks!


Tried to do some digging

So the CPU will directly connect to the GPU with 16x 4.0 and 4x for 1 NVME drives,
the chipset itself extends 10 3.0 lanes, the question becomes, are any of the NVME drives connected to the 3.0 lanes? IF so a B550 board would cut it for me.
 
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mda

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How a B550 works:

Except for the Aorus B550 Master (which has a funky PCIE 4.0 splitting mechanism in place):
You get a 16x PCIE 4.0 for the GPU and x4 PCIE 4.0 from the CPU

The B550 chipset itself gets 10 additional PCIE 3.0 lanes.
How it splits those up is up to the board implementation

https://www.gamersnexus.net/guides/3582-amd-chipset-differences-b550-vs-x570-b450-x470-zen-3

Short answer, depending on the board, and since most WIFI cards should use only a PCIE 2.0/3.0 X1 connection, a B550 should do it for you unless you use more than 4 SATA devices.

CPU lanes
PCIE 4.0 x16 - GPU
PCIE 4.0 x4 - M.2

Chipset Lanes
PCIE 3.0 x1 - WIFI
PCIE 3.0 X4 - M.2

Lots of boards that should work for you, but take note that some boards already have baked in WIFI chips.
 

kirbyrj

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You definitely have to check the board manual to see how the lanes are split because they are all different.
 

Ready4Dis

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If it has 2 NVME's and it's a B550, there is a good chance it's 3.0 x4. Of course double check, but this is the most common setup. You don't have to run your GPU @ x8 to use an NVME on AMD platforms. Sometimes you will lose a SATA port or two if you use the second NVME just an FYI (similar as Intel). x570 boards aren't to much more and they have dual NVME pcie 4.0 (one via chipset, one direct to CPU). So may be worth looking into depending on your budget.
 

E4g1e

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I currently have an 8700k with a Z370 board.
Currently running 2 NVME drives, 1 PCIe Wifi card + my GPU, the GPU is forced down to 8x with this setup. Would a B550 allow me to run 16x on the gpu? also does it support PCIe 4.0 for the GPU since it comes directly from the CPU?

Thanks!
Check the slot where your PCIe WiFi card is inserted into. If your motherboard splits its PCIe bifurcation to split the CPU-direct PCIe controller to two x8 slots or one x8 plus two x4 slots, and you do not have any available (free) PCIe x1 or x4 slots available, and you are forced to use one of the bifurcated x16 slots, then yes. Your main PCIe x16 slot will be forced down to x8.

Your m.2 SSDs do not matter, in this case, since all Intel mainstream CPU platforms run all of their m.2 slots off of the chipset instead of directly off of the CPU.
 

Digital Viper-X-

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I was considering the X570, buttttt, preferred something with a passive solution for the chipset.

Depending on the price of the Dark Hero VIII, I may just go for that.

Thanks all.
 

Dan_D

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If it has 2 NVME's and it's a B550, there is a good chance it's 3.0 x4. Of course double check, but this is the most common setup. You don't have to run your GPU @ x8 to use an NVME on AMD platforms. Sometimes you will lose a SATA port or two if you use the second NVME just an FYI (similar as Intel). x570 boards aren't to much more and they have dual NVME pcie 4.0 (one via chipset, one direct to CPU). So may be worth looking into depending on your budget.
Any B550 board with two M.2 slots would have one of them running at PCIe 4.0 x4 and the other at PCIe 3.0 x4. There is only one dedicated M.2 slot that connects to the PCIe 4.0 lanes on the CPU. Although, it can be split and reduced to 2x lanes, this is never done.
I was considering the X570, buttttt, preferred something with a passive solution for the chipset.

Depending on the price of the Dark Hero VIII, I may just go for that.

Thanks all.
The chipset fans aren't really all that loud. You might hear them on startup, but they tend to operate slow enough that they aren't really a bother. I've been testing X570 boards since they came out and have had quite a few cross my test bench. I have yet to have one fail or make any discernable noise outside of the initial power on. I run these on an open test bench and still don't hear them. My MSI MEG X570 GODLIKE is in a case and I've never heard it.
 

Digital Viper-X-

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Thanks for the input, I guess I'm a bit gun shy from the days of yore, where the chipset fans would eventually fail
 

Dan_D

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Thanks for the input, I guess I'm a bit gun shy from the days of yore, where the chipset fans would eventually fail

The chipset fans on X570 don't even run all the time. The chipset has to reach about 60c for them to kick on. When they do, they run at fairly low speeds to keep them right under 60c.
 

Ready4Dis

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Any B550 board with two M.2 slots would have one of them running at PCIe 4.0 x4 and the other at PCIe 3.0 x4. There is only one dedicated M.2 slot that connects to the PCIe 4.0 lanes on the CPU. Although, it can be split and reduced to 2x lanes, this is never done.

The chipset fans aren't really all that loud. You might hear them on startup, but they tend to operate slow enough that they aren't really a bother. I've been testing X570 boards since they came out and have had quite a few cross my test bench. I have yet to have one fail or make any discernable noise outside of the initial power on. I run these on an open test bench and still don't hear them. My MSI MEG X570 GODLIKE is in a case and I've never heard it.
I haven't looked into all of them, I know a while back (older gens) some nvme slots were only SATA, wasn't sure if any still had that odd layout, which is why i left it slightly open as I haven't scoped out all the board specs. I only knew all of the ones I looked into were pcie and was figuring that would be the case in pretty much all instances, but I don't like to guess even if I'm like 99.9% sure.
 

Dan_D

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I haven't looked into all of them, I know a while back (older gens) some nvme slots were only SATA, wasn't sure if any still had that odd layout, which is why i left it slightly open as I haven't scoped out all the board specs. I only knew all of the ones I looked into were pcie and was figuring that would be the case in pretty much all instances, but I don't like to guess even if I'm like 99.9% sure.

The SATA only slots date back to the Z97 and earlier chipsets. By Z170, this was no longer an issue. AMD never did this with X370 or newer chipsets either. However, many M.2 slots on newer boards do contain SATA M.2 compatibility. Usually, only one of two or three slots provided will support those devices.
 

Ready4Dis

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The SATA only slots date back to the Z97 and earlier chipsets. By Z170, this was no longer an issue. AMD never did this with X370 or newer chipsets either. However, many M.2 slots on newer boards do contain SATA M.2 compatibility. Usually, only one of two or three slots provided will support those devices.
Yeah, like I said, I haven't checked all board specs so I said most will but double check. I was 99.9% sure, but I'd rather not blanket statement and figure out some weird cheap board did something like that. Anyways, good to know though, I figured as much already but like I said, I don't like to tell people I'm positive if I haven't verified it personally.
 

vegeta535

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I was considering the X570, buttttt, preferred something with a passive solution for the chipset.

Depending on the price of the Dark Hero VIII, I may just go for that.

Thanks all.
They are passive cooled. The fan almost never runs.
 

thesmokingman

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Thanks for the input, I guess I'm a bit gun shy from the days of yore, where the chipset fans would eventually fail

There's way too many ppl that think like this on the topic of chipset fans. The reality is it's a non-issue. And the obvious point is these ppl are ignoring the reason the fan is there. PCIE4 on the chipset is actually hard, thus the fan is there just in case. That why the B550 doesn't have a fan, it isn't GEN4.
 

mda

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Maybe for Dan_D but also for the rest of the people who have done some in depth testing with these boards...

As a worst case scenario, if the fans do fail --

How likely is the stock heatsink going to hold up with the X570 boards?

Not trying to fan smoke post, it's just that I keep my builds running far longer than most (My AMD Newcastle build just stopped running 2-3 years ago, my Q6600 is here with a sibling) and I do not live in the USA where you can probably request a few from the larger board companies.
 

thesmokingman

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Maybe for Dan_D but also for the rest of the people who have done some in depth testing with these boards...

As a worst case scenario, if the fans do fail --

How likely is the stock heatsink going to hold up with the X570 boards?

Not trying to fan smoke post, it's just that I keep my builds running far longer than most (My AMD Newcastle build just stopped running 2-3 years ago, my Q6600 is here with a sibling) and I do not live in the USA where you can probably request a few from the larger board companies.

The fan barely does anything. If you look closely at the pics of some of these boards the fan fins are vertical, pushing air horizontally instead of down into the sink. Sometimes I wonder why they even bothered but maybe minimal airflow is enough? Or its a CYA situation. In a worse case scenario just be mindful to direct some airflow in that direction. Also, in some cases boards with these fans do not even run after the board is booted so is it really needed? They slapped one into the specification so I'm leaning towards a CYA, just in case.

The new CH8 Dark board doesn't use a fan but instead a larger heatsink. That makes some sense since they the heatsink would have to work in any situation including one with little to no airflow.
 

merid14

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Maybe for Dan_D but also for the rest of the people who have done some in depth testing with these boards...

As a worst case scenario, if the fans do fail --

How likely is the stock heatsink going to hold up with the X570 boards?

Not trying to fan smoke post, it's just that I keep my builds running far longer than most (My AMD Newcastle build just stopped running 2-3 years ago, my Q6600 is here with a sibling) and I do not live in the USA where you can probably request a few from the larger board companies.
I’m in the same boat. My i7 920 just died a year ago and it was running with a fan strapped to the chipset. I’ve been running a cobbled together 3570. I’m looking at the b550 or the x470.
 

thesmokingman

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I’m in the same boat. My i7 920 just died a year ago and it was running with a fan strapped to the chipset. I’ve been running a cobbled together 3570. I’m looking at the b550 or the x470.

On my old RIVE I used the minimal chipset block from EK. That's the one that only used a block for the vrms and replaced the chipset fan with a heatsink and the heatsink wasn't very big either and definitely smaller than the contraption Asus used. Years later after retiring it, I noticed that the heatsink did go thru some heat cycles due to the discoloration but beyond that everything was flawless. Back then I was benching on quad gpus so if it was gonna melt the chipset it had ample opportunities to do so but it never brought any attention to itself.
 

Digital Viper-X-

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So, Asus just delivered if you want to shell out some $$.

Crosshair VIII Dark Hero is a passively cooled X570 board.
 

Dan_D

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On the subject of X570 chipset fans:

The fans do engage on occasion. When they do, they typically spin at fairly low speeds. I think the airflow is simply a CYA type of situation. It was cheaper to do that then to make better passive heat sinks. However, there are a couple of motherboars with passive heat sinks for X570 chipsets. So, we know it can be done. To be clear, I doubt these fans will matter for enthusiasts who keep PC's on their desks, don't keep their apartments or houses above 75F ambient. For gamers who buy prebuilts or boutique systems that might get shoved into cabinets in cheap Wal-Mart desks, I can see chipset failure as being a problem. If your a hoarder who uses your PC as a book shelf or something it might be an issue.

Keep in mind, these fans aren't the same ones that we had on chipsets back in the Pentium III days. They are also not necessarily required. I think they tend to be there due to the fact that the X570 chipset is somewhat borderline on the heat issue. It pulls three times as much power as most modern PCH's do. Those fans probably extend the life of the chipset some by keeping it under a certain threshold. In this case, all of the ones I've seen run at about 60C or thereabouts. That seems to be their target temperature.
 
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