NVMe for OS storage

[TatamiMatt]

I recently got a second NVMe for very cheap, currently have a 1TB SN850 for game storage and im looking to upgrade to a sabrent rocket 4-plus g 2tb as space is getting low fast with game sizing constantly on the rise. The cheap drive I picked up is a 500GB WD Blue sn 570.

 

My main question is at what point does drive speed produce diminishing returns for OS storage and boot, should i wait until i get the new Sabrent and repurpose my sn850 (7000mbps) for os storage and boot or just swap OS over now and work off the WD Blue (3500mbps). Will the extra speed from the SN850 be noticeable? (Also motherboard has 3 NVMe slots so all 3 will be used in some way, side question, does this split bandwidth between NVMe slots and is it worth using all 3 slots in this scenario? If so NVMe can be repurposed to a second build. Motherboard is MSI MAG B650 Tomahawk)

[filpo]

8 minutes ago, TatamiMatt said:

Will the extra speed from the SN850 be noticeable?

for OS boot times? No most likely not since the sn850 doesn't have any dram cache

 

9 minutes ago, TatamiMatt said:

does this split bandwidth between NVMe slots

some of the communication may just go through the chipset (the top nvme slot is normally always directly connected to the CPU)

 

10 minutes ago, TatamiMatt said:

is it worth using all 3 slots in this scenario?

if you want/need the extra storage then sure

[TatamiMatt]

15 minutes ago, filpo said:

for OS boot times? No most likely not since the sn850 doesn't have any dram cache

 

some of the communication may just go through the chipset (the top nvme slot is normally always directly connected to the CPU)

 

if you want/need the extra storage then sure

Does the sn570 have any DRAM cache? and if not, does that change which will be faster?

 

So the 2 and 3 slots are both fine to load drives into and it wont affect speeds?

[venomtail]

Windows OS only cares about Random Read write speeds. Those advertised speeds are usually sequential, really useful when you're transferring over a 1TB file. DRAM is usefull of quickly copy pasting files on the drive.

 

These random read writes are hard to improve and thus improve a bit by bit each generation, not enough to really notice a huge change in using windows.

[TatamiMatt]

2 minutes ago, venomtail said:

Windows OS only cares about Random Read write speeds. Those advertised speeds are usually sequential, really useful when you're transferring over a 1TB file. DRAM is usefull of quickly copy pasting files on the drive.

 

These random read writes are hard to improve and thus improve a bit by bit each generation, not enough to really notice a huge change in using windows.

Thanks thats handy to know.

 

Do you reckon there would be a noticeable difference between 7000/5300 (SN850 mbps) vs 3500/2300 (SN570 mbps) for OS boot then?

[filpo]

11 minutes ago, TatamiMatt said:

Does the sn570 have any DRAM cache?

no it doesn't

 

12 minutes ago, TatamiMatt said:

does that change which will be faster?

the sn570 might be a bit slower but by 'a bit slower' it'll be like 0.5 seconds longer in booting to OS

12 minutes ago, TatamiMatt said:

So the 2 and 3 slots are both fine to load drives into and it wont affect speeds?

I'd put your fastest drive in the top slot and then put your slowest one in the bottom slot. And the middle one in the middle ofc

[Tan3l6]

1 minute ago, TatamiMatt said:

Thanks thats handy to know.

 

Do you reckon there would be a noticeable difference between 7000/5300 (SN850 mbps) vs 3500/2300 (SN570 mbps) for OS boot then?

Not really. Not if you aren't using very precise stop-clock/timer. Talking about milliseconds probably.

[TatamiMatt]

1 minute ago, filpo said:

no it doesn't

 

the sn570 might be a bit slower but by 'a bit slower' it'll be like 0.5 seconds longer in booting to OS

I'd put your fastest drive in the top slot and then put your slowest one in the bottom slot. And the middle one in the middle ofc

Yeah was going to order them by speed, i think the B650 tomahawy boards M.2 slot 3 is actually the middle one from what i can make out?

[filpo]

1 minute ago, TatamiMatt said:

3 is actually the middle one from what i can make out?

if that's what it says in the manual follow that

[will0hlep]

Dram cache is irrelivant in tasks that involve only reading. It is used to allow for fast writing of very large files, it has almost no effect on read speeds.

 

Booting is a mixture of random and sequential reads. Unfortuantly random reads arn't sped up much by using an NVMe drive. The sequential reads are sped up, and I believe microsoft have spent some time optimising windows so much of the on boot reads are sequential. However, a faster NVMe drive still won't actually save much time cause your reaching the point of deminishing returns.

 

Atm the best value for money in my opinion is the Cruicial P3. You can go PCIe gen 4 but I doubt you'll ever notice the difference.

[Tan3l6]

5 minutes ago, TatamiMatt said:

Yeah was going to order them by speed, i think the B650 tomahawy boards M.2 slot 3 is actually the middle one from what i can make out?

Whitch do you think is "3"?

[will0hlep]

M.2_1 Source (From CPU) supports up to PCIe 4.0 x4 , supports 2280/2260 devices
M.2_2 Source (From CPU) supports up to PCIe 4.0 x4 , supports 2280/2260 devices
M.2_3 Source (From Chipset) supports up to PCIe 4.0 x4 , supports 2280/2260 devices

M.2_1 and M.2_2 are typically going to be faster than M.2_3 because they don't go through the chipset (but I doubt you'd ever actually notice a difference).

Source: https://www.msi.com/Motherboard/MAG-B650-TOMAHAWK-WIFI/Specification

[Tan3l6]

3 is the last one to occupy. 1 is the most consistent as far as I know.

[TatamiMatt]

Thanks all, to be honest, I've only glanced over the board once, I'm putting it together this weekend, the 3 slot comes with a heatsink so I assumed this would be the faster out of the 2 and 3 slots, haven't actually looked at anything in detail yet! I'll probably put windows on the sn570 in slot 3 then, the sn850 in the 2 slots which works well with it having a built in heatisnk and no mobo heatsink in that slot, and finally the sabrent when I get it in the 1st slot

 

Thanks again for the help!

[ewitte]

6 hours ago, venomtail said:

Windows OS only cares about Random Read write speeds. Those advertised speeds are usually sequential, really useful when you're transferring over a 1TB file. DRAM is usefull of quickly copy pasting files on the drive.

 

These random read writes are hard to improve and thus improve a bit by bit each generation, not enough to really notice a huge change in using windows.

Any time I've tried a dramless drive system responsiveness feels a lot more laggy...  I had a "Samsung 980" briefly on one machine and returned it.