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Question x570 and NVMe Slot Latency (Chipset vs CPU Lanes Slot)

Dave3000

Golden Member
Jan 10, 2011
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Does the lower (chipset lanes) NVMe slot have the same latency as the NVMe slot closet to the CPU (CPU lanes)? I know both slots have PCI-E 4.0 support, so same bandwidth in both slots on x570. Also if I decided to get an x570 motherboard and 2 NVMe drives, one small one strictly for the OS and a huge one for Data such as my games, music, and work files, should I put the OS drive on lower NVMe slot (chipset lanes) and the Data drive on the NVMe slot closet to the CPU (CPU lanes) or does it really not matter?
 

damian101

Senior member
Aug 11, 2020
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I would expect there to be a lot of additional latency for chipset PCIe lanes, but I think it's pretty much meaningless for Nvme SSD performance. PCIe latency lies in the hundreds of nanoseconds, while it takes at least tens of microseconds to read a single 4KiB sector from a very fast Nvme SSD.
The shared bandwidth might have an effect though, the chipset is only connected to the CPU with 4 PCIe 4 lanes. Everything connected to the chipset uses that connection.
 
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Dave3000

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Jan 10, 2011
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Maybe in that case I'm just better off getting a good quality B550 motherboard and one large PCI-E 4.0 NVMe drive, not buying a small NVME for the OS, and just setup partitions as a dedicated OS partition on it and a dedicated Data partition and using the NVMe slot closest to the CPU?
 

Dave3000

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Jan 10, 2011
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Maybe I'll just go for a B550 motherboard and a single large NVMe PCI-E 4.0 drive. I'm waiting for the Samsung 980 Pro 2TB to be released.
 

UsandThem

Elite Member
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I'm waiting for the Samsung 980 Pro 2TB to be released.
Why? It's going to be priced high compared to the competition, without being faster or offering a longer/better warranty like the days when it used MLC NAND. If what I read is correct on the pricing, the 2TB version is going to be close to $600.

I wouldn't spend that kind of money for a 2TB drive, when you can get a PCIe 3.0 2TB drive for roughly 1/3rd of that price. Running synthetic benchmarks are cool and all, but that's quite the performance tax. :oops:
 

Dave3000

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Jan 10, 2011
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I wouldn't mind buying a Samsung 970 EVO+ 2TB instead of the 980 Pro 2TB if the price difference is going to be that big. However, PS5 and XBox One SX have a PCI-E 4.0 NVMe and with Direct Storage feature coming out, I don't now if a PCI-E 3.0 NVMe will be much slower at loading levels and zones into memory than a PCI-E 4.0 NVMe. Should I just ignore the hardware of the consoles when it comes to PC gaming?
 

UsandThem

Elite Member
Super Moderator
May 4, 2000
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I wouldn't mind buying a Samsung 970 EVO+ 2TB instead of the 980 Pro 2TB if the price difference is going to be that big. However, PS5 and XBox One SX have a PCI-E 4.0 NVMe and with Direct Storage feature coming out, I don't now if a PCI-E 3.0 NVMe will be much slower at loading levels and zones into memory than a PCI-E 4.0 NVMe. Should I just ignore the hardware of the consoles when it comes to PC gaming?
I'm not into console gaming, and the only thing I know about subject was reading an article saying the new Xbox required the use of a proprietary external hard drive for expansion. As far as Sony, I think they allow the use of normal NVMe drives, but someone else would have to answer about the speed aspect of PCIe 3.0 vs 4.0 concerning the Playstation.
 

beginner99

Diamond Member
Jun 2, 2009
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Why? It's going to be priced high compared to the competition, without being faster or offering a longer/better warranty like the days when it used MLC NAND. If what I read is correct on the pricing, the 2TB version is going to be close to $600.
Agree. The 980 Pro was underwhelming honestly. Made me feel much better about my 970 pro purchase about 1.5 years ago were I wasn't sure if I should wait for a pcie4 version or not. MLC all the way.
 
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UsandThem

Elite Member
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May 4, 2000
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Agree. The 980 Pro was underwhelming honestly. Made me feel much better about my 970 pro purchase about 1.5 years ago were I wasn't sure if I should wait for a pcie4 version or not. MLC all the way.
For all intents and purposes, it's really just a 980 EVO marauding as a PRO.

It's still a good drive, but it in no way demands the premium Samsung is charging for it.
 

damian101

Senior member
Aug 11, 2020
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Maybe in that case I'm just better off getting a good quality B550 motherboard and one large PCI-E 4.0 NVMe drive, not buying a small NVME for the OS, and just setup partitions as a dedicated OS partition on it and a dedicated Data partition and using the NVMe slot closest to the CPU?
PCIe 4 Nvme drives are still very expensive and from my understanding don't provide any meaningful performance increase for the average user compared to fast PCIe 3 or even SATA SSDs. For gaming performance that might change with special DirectStorage implementations, but until then prices for PCIe 4 SSD will have dropped. My games are still all on a (dedicated) HDD as saving a few seconds in load times doesn't justify buying an expensive 4TB SSD for me. That might also change with DirectStorage.
I see no point in creating an additional data partition on the same drive, unless you want to share data between different operating systems. Just creating a dedicated directory for that makes more sense to me. At least for Steam games it's very easy to later move the game library to a different path anyway.
X570 has twice the chipset bandwidth compared to B550, which can make a difference even with PCIe 3.0 SSDs.
 

Dave3000

Golden Member
Jan 10, 2011
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I was thinking about the MSI Tomahawk X570 for an x570 motherboard. Well, today I purchased a Samsung 970 EVO Plus 250GB NVMe for the Windows 10 operating system and a few basic apps. I'll still use my Samsung 850 EVO 2TB SATA as my data/games drive and eventually replace that one with maybe a 970 EVO Plus 2TB or possibly a 980 Pro 2TB. I don't know, maybe with two PCI-E 3.0 NVMe drives, X570 is a waste, and B550 is be adequate for this situation? I'm thinking about either getting an Asus Strix B550-F (Wi-Fi), MSI B550 Carbon or a MSI x570 Tomahawk motherboard.

PCIe 4 Nvme drives are still very expensive and from my understanding don't provide any meaningful performance increase for the average user compared to fast PCIe 3 or even SATA SSDs. For gaming performance that might change with special DirectStorage implementations, but until then prices for PCIe 4 SSD will have dropped. My games are still all on a (dedicated) HDD as saving a few seconds in load times doesn't justify buying an expensive 4TB SSD for me. That might also change with DirectStorage.
I see no point in creating an additional data partition on the same drive, unless you want to share data between different operating systems. Just creating a dedicated directory for that makes more sense to me. At least for Steam games it's very easy to later move the game library to a different path anyway.
X570 has twice the chipset bandwidth compared to B550, which can make a difference even with PCIe 3.0 SSDs.
The way I have my drives setup right now is I have a 250GB SSD for Windows and basic apps, and my data and games on a 2TB SSD in a single partition but with a Games parent folder and a Data parent folder. I don't see the point either in having a dedicated partition for games and data in one physical drive as long as the operating system is on it's own physical drive or partition away from the games and data.
 

Shmee

Memory and Storage, Graphics Cards
Super Moderator
Sep 13, 2008
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If you want the best, you gotta pay. The 980 Pro is the best right now. Did you read the review?

You don't say which X570 board you're looking at, but in my Asrock X570, there are 3 M.2 slots, 2 of which support PCI-E 4.0 NVMe. Check the manual of your board choice before you buy.
I don't think the 980 Pro is currently the best. The Sabrent Rocket 4 Plus 2TB is a bit faster, and there is no 2TB version of the 980 Pro yet I believe.
 

Justinus

Platinum Member
Oct 10, 2005
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I don't think the 980 Pro is currently the best. The Sabrent Rocket 4 Plus 2TB is a bit faster, and there is no 2TB version of the 980 Pro yet I believe.
Pretty sure the SN850 and Rocket 4 Plus are both neck and neck vs. the 980 Pro. The Rocket is stronger at writes and weaker at reads while the SN850 is stronger at reads and competitive at writes.

Both make a superior option to the (yet to be released) 980 Pro 2TB because, well, they are readily available for immediate purchase and both can be had around $400 for the 2TB version. Good luck with the 980, it will be $450-500 or more.

Not to mention the principle of the issue - Samsung carefully cultivating the Pro branding for damn near a decade only to literally throw it away on a next gen TLC drive? It's very short sighted.

If they still had a killer, market leading product you could probably justify it as "it's still the best" but as I stated before, the competition is fierce, both technically and fiscally superior.
 

Shmee

Memory and Storage, Graphics Cards
Super Moderator
Sep 13, 2008
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Yeah I forgot about the SN850 for a moment, which is another good alternative.
 

beginner99

Diamond Member
Jun 2, 2009
4,750
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Not to mention the principle of the issue - Samsung carefully cultivating the Pro branding for damn near a decade only to literally throw it away on a next gen TLC drive? It's very short sighted.

If they still had a killer, market leading product you could probably justify it as "it's still the best" but as I stated before, the competition is fierce, both technically and fiscally superior.
So true. Fully explains why the 980 Pro is really underwhelming. It's nothing special neither in performance nor anything else. I can then simply ignore it and buy a cheaper TLC drive with essentially the same performance and endurance.
 

thesmokingman

Platinum Member
May 6, 2010
2,305
230
106
Does the lower (chipset lanes) NVMe slot have the same latency as the NVMe slot closet to the CPU (CPU lanes)? I know both slots have PCI-E 4.0 support, so same bandwidth in both slots on x570. Also if I decided to get an x570 motherboard and 2 NVMe drives, one small one strictly for the OS and a huge one for Data such as my games, music, and work files, should I put the OS drive on lower NVMe slot (chipset lanes) and the Data drive on the NVMe slot closet to the CPU (CPU lanes) or does it really not matter?
It doesn't matter. There's no latency penalty and it's not important anyways. There's so much bandwidth, it won't matter unless you're running a big array off of it which you can't really do anyways so no worries.
 

Muadib

Lifer
May 30, 2000
16,698
402
126
I don't think the 980 Pro is currently the best. The Sabrent Rocket 4 Plus 2TB is a bit faster, and there is no 2TB version of the 980 Pro yet I believe.
You are correct about the 2TB 980 Pro. They were taking pre orders for both the 980 Pro & the SN850 when I was looking back in December, and I don't know if they shipped yet.
 

Dave3000

Golden Member
Jan 10, 2011
1,048
37
91
I decided that I will go with 2 Samsung 970 EVO Plus NVMe SSDs, a 250GB one (already purchased) for the OS, and a 2TB one for Games/Data. I want full PCI-E 3.0 bandwidth for both NVMe SSDs installed on the motherboard, and keeping the full PCI-E 4.0 x16 lanes for the graphics card. I understand that the NVMe chipset-connected slot shares the PCI-E 3.0 bandwidth with other chipset-connected devices at the PCH level through DMI but does that lower the amount of lanes dedicated to the chipset-connected NVMe SSD, for example will it cause the chipset-connected NVMe SSD to run at PCI-E 3.0 x2 instead of PCI-E 3.0 x4? Does a B550 chipset motherboard provide that or do I need to get an x570 chipset motherboard to provide that, as in full PCI-E 3.0 lanes to both NVMe drives while maitaining PCI-E 4.0 x16 lanes to the GPU or do I need an x570 motherboard to achieve that?
 
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thesmokingman

Platinum Member
May 6, 2010
2,305
230
106
I decided that I will go with 2 Samsung 970 EVO Plus NVMe SSDs, a 250GB one (already purchased) for the OS, and a 2TB one for Games/Data. I want full PCI-E 3.0 bandwidth for both NVMe SSDs installed on the motherboard, and keeping the full PCI-E 4.0 x16 lanes for the graphics card. I understand that the NVMe chipset-connected slot shares the PCI-E 3.0 bandwidth with other chipset-connected devices at the PCH level through DMI but does that lower the amount of lanes dedicated to the chipset-connected NVMe SSD, for example will it cause the chipset-connected NVMe SSD to run at PCI-E 3.0 x2 instead of PCI-E 3.0 x4? Does a B550 chipset motherboard provide that or do I need to get an x570 chipset motherboard to provide that, as in full PCI-E 3.0 lanes to both NVMe drives while maitaining PCI-E 4.0 x16 lanes to the GPU or do I need an x570 motherboard to achieve that?
There's no DMI, that's intel which is their proprietary link. On AMD it's connected using pcie4 on x570 and on 550 its pcie3. If you are staying on gen3 the 550 will be fine I suppose.

 

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