M.2 slots

sargan

sargan

sargan

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Probably pretty basic questions to those that know.

Not had M.2 support before on a PC so new to me.
Thinking of new build and had advice here to consider using AS Rock B650 Taichi Lite
This has its seems 1 x PCIe 5.0, and 4 x PCIe 4.0 x4

Does this mean that I should put a large capacity PCIE 5 M2 card as my main 'storage' OS/Applications
Would the PCIE4 then be used for saved files / archive etc.

Similar to the way in current PC I have C:/ as OS & Apps and D:/ for videos, pictures, music etc.
 
Not sure you will notice much difference
Using a pcie5 over a pcie 4
If you had more than 1 pcie5 then yeah
Copying files between them would be faster

How big your main drive is
That will depend
Do you put your games on c drive?
And what's a "large capacity"to you?
A lot of people would do say 1tb for c drive
2tb for storage
Another 2tb maybe for backups
And so forth
Everyone has different storage requirements
There's no you must do it in 1 particular way
Me I have 5 x m2 and 4 x 2.5 sata ssds
Doesn't mean everyone has to do that
 
There are very few use cases that buying a PCI-E 5.0 drive makes sense, you get way more performance putting your money into other things like the CPU & GPU.
 
This is not meant to be an argument point, I thought PCIE5.0 next to CPU can handle data at least 2.5 times faster ? or that Is what I had read. For my needs I will be putting money into the CPU as that will have greater performance gains than putting big money on an expensive GPU. Most of my work that needs power will be video processing with Davinci.
As the slot is there anyway ... would you advise not bothering to buy PCIE 5 storage and put PCIE 4 in that slot ?
 
2.5 x faster
That may be talking about latency
Not read and write
With latency already in almost instantaneous figures
Will 2.5 x faster actually be noticeable

Other thing with pcie5
Will be heat and possible throttling
Does davinci use some sort of temp/scratch file on c drive?
Pcie5 might matter then
But I don't have a pcie5 drive or use davinci
So can't say from personal experience
 
sargan said:
My comment on 2.5 times faster was for Read Write speed .... I had seen this:
www.corsair.com

PCIe 5.0 vs PCIe 4.0 NVMe M.2 SSDs: What's the difference?

With PCIe Gen 5 M.2 SSDs becoming more available, we're going to look at the differences of Gen 4 vs Gen 5.
www.corsair.com www.corsair.com
Click to expand...
Sorry I misread what you meant
Thought you meant was 2.5 x faster due to being
In slot nearest the cpu
Ie compared to another pcie5 drive in a slot
That ran off the chipset

Would probably still come back to
Does davinci use a temp/scratch file on c drive then
Or do users put those on a second drive
And if so we still have the Will it overheat and throttle question

Or is there space to put an aftermarket heatsink on the pcie5 m2 slot?
 
sargan said:
This is not meant to be an argument point, I thought PCIE5.0 next to CPU can handle data at least 2.5 times faster ? or that Is what I had read. For my needs I will be putting money into the CPU as that will have greater performance gains than putting big money on an expensive GPU. Most of my work that needs power will be video processing with Davinci.
Click to expand...
4 lanes of PCI-E 4.0 is around 8 GB/s and 4 lanes of PCI-E 5.0 is around 16 GB/s, so in theory they can read and write a lot more, but realistically you have two problems:
1. The bandwidth available is only a small part of the technology, since e.g. you need a controller and flash that can handle those speeds,
and
2. Few workloads adequately saturate the drive in a way that you see a meaningful benefit.

With Davinci specifically, I'd have a look at your task manager while you're working on your projects and I suspect you'll find that the bottleneck is not normally your SSD.

sargan said:
As the slot is there anyway ... would you advise not bothering to buy PCIE 5 storage and put PCIE 4 in that slot ?
Click to expand...
Yes, likely to be the best value for money.
 
The other thing
What size disk will you need?
There's a large price difference between pcie 4 and 5
If you need 4tb or 8tb
Pcie5 will be a lot more expensive

Now my memory isn't the greatest
So may be wrong
Did I see you mention doing this stuff at work also?
If so what hardware do work use?
Assuming I am not getting mixed up with someone else's post
Which is quite possible
 
Tetras said:
4 lanes of PCI-E 4.0 is around 8 GB/s and 4 lanes of PCI-E 5.0 is around 16 GB/s, so in theory they can read and write a lot more, but realistically you have two problems:
1. The bandwidth available is only a small part of the technology, since e.g. you need a controller and flash that can handle those speeds,
and
Click to expand...
Just watching a review of PCIe M.2 ssd, they said that on the motherboard there was one M.2 socket (next to CPU) that dose not use the controller, data lines go direct to the CPU. So you get the high r/w performance.
The other M.2 sockets are connected to the controller ?
 
sargan said:
Just watching a review of PCIe M.2 ssd, they said that on the motherboard there was one M.2 socket (next to CPU) that dose not use the controller, data lines go direct to the CPU. So you get the high r/w performance.
The other M.2 sockets are connected to the controller ?
Click to expand...
I think they're referring to the chipset. By "controller" I meant, the controller on the drive itself.
 
The kind and quality of the M.2 matters more, does it have DRAM cache, which chipset is it. A good M.2 in a gen 3 slot is still going to perform very well for the vast majority of people.
 
sargan said:
OK ...Thnx .... trying to learn about M 2 SSD's
Click to expand...
An M.2 drive has a controller on the drive that determines performance, together with the flash itself.

The PCI-E version gives you like... an upper threshold on what is possible, but it doesn't actually describe the performance of the drive.

For example: you could have a canyon with lots of room for water, but only a small stream at the bottom. This describes a PCI-E 5.0 drive with a poor controller and/or slow flash.

AND, a lot of things that you do with your PCI-E 5.0 drive need very small amounts of data (i.e. they're just a small stream anyway), so having the potential to fill a canyon means nothing.
 
Meaker said:
Depends on your usage to be fair, is it a primary drive, a game storage drive, what's the budget?
Click to expand...
I don't have a budget other than keep total build under 2k. The performance loading will be from video editing. Looking to get a suitable SSD to match Ryzen R9.
It would seem sensible to have the highest performing SSD in the PCIe5,o slot as this has a direct connection to CPU - assume a 1TB in that slot
Then a 2TB SSD in one of the PCIe4.0 slots
 
Tetras said:
An M.2 drive has a controller on the drive that determines performance, together with the flash itself.

The PCI-E version gives you like... an upper threshold on what is possible, but it doesn't actually describe the performance of the drive.

For example: you could have a canyon with lots of room for water, but only a small stream at the bottom. This describes a PCI-E 5.0 drive with a poor controller and/or slow flash.

AND, a lot of things that you do with your PCI-E 5.0 drive need very small amounts of data (i.e. they're just a small stream anyway), so having the potential to fill a canyon means nothing.
Click to expand...
So what data figures do I need to look at to find a PCIe SSD with a controller with better performance ... is it the read/write speed ? The PCIe5.0 SSD that I have been looking at all use the E26 Phison controller, which seem to be the best.
The Crucial T700 is one I had been considering.
Sort of lucky I have 2 weeks at least before I order (holding off my decision until Ryzen CPU launch date) ... so hope to get this right, hence my questions.
 
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For the price of the Taichi lite you can get a decent X670E, I know it was recommended on the HW unboxed video but that was at $240 USD which is around £190, over here it seems to be £100 more expensive which makes it a hard sell imo.
 
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