Large capacity M.2 or SSD?

[Kronos]

I currently have a Samsung 960 EVO (250GB) M.2-2280 PCI Express 3.0 as my C drive but think that I might prefer something bigger to put games on as one or two do not seem to play nice on another SSD.

Should I get a larger capacity M.2 or use a large capacity SSD?

 

[voidshatter]

I would prefer a larger NVME M.2, as SATA SSD would have a speed cap by the interface.

Multiple drives and multiple partitions would decrease the capacity efficiency, because you always waste the last tens of gigabytes of each partition.

 

[mrbazmondo]

I would prefer a larger NVME M.2, as SATA SSD would have a speed cap by the interface.

I read another thread recently where the M2 was getting speed capped because the m2 ports were on pcie express lanes attached to the chipset rather than the processor.

 

[voidshatter]

I read another thread recently where the M2 was getting speed capped because the m2 ports were on pcie express lanes attached to the chipset rather than the processor.

NVME M.2 SSD can achieve 2500MB/s speed, while SATA SSD can only achieve 500MB/s speed. It's 5x difference.

 

[chroniclard]

Just add a large SSD, wont notice any speed from the M.2 in real world usage.

 

[Mr Jack]

Just add a large SSD, wont notice any speed from the M.2 in real world usage.

Yup, this. Unless you're doing hardcore bioinformatics or something you won't need it and won't notice it.

 

[mrbazmondo]

NVME M.2 SSD can achieve 2500MB/s speed, while SATA SSD can only achieve 500MB/s speed. It's 5x difference.

PCIe 2,0 is 500MB/s a lane. M2 is 4 lanes, so going via the chipset instantly drops you to 2000MBs. The bandwidth between the CPU and the chipset introduces more latency and is also shared with other devices on the chipset, so this can reduce the bandwidth further.

Even though the 960 reports a speed in excess of 3GBs you won't achieve that for small file transfers such as booting. Large file transfers maybe, such as loading large amount of data when starting a game.

 

[voidshatter]

introduces more latency

This is false. NVME has less latency. For example:

Samsung 850 PRO 2TB (SATA) has 0.09ms latency:

Samsung 960 PRO 2TB (NVME) has 0.04ms latency:

Some examples of NVME throughput:

Samsung 960 PRO 2TB (NVME) installing a steam game and pre-allocating at 1.3GB/s:

Samsung 960 PRO 2TB (NVME) defragmenting a disk of a virtual machine at 1.9GB/s:

 

[mrbazmondo]

This is false.

In what world does NVMe connected to a chipset, connected to a CPU not have more latency than NMVe on PCIe 3.0 lanes connected directly to the CPU?

 

[voidshatter]

In what world does NVMe connected to a chipset, connected to a CPU not have more latency than NMVe on PCIe 3.0 lanes connected directly to the CPU?

I have no idea what you are talking about. I trust my numbers, measured on my own computer with my own SSDs. NVME has shown less than half of the latency of SATA (0.04ms vs 0.09 ms, no rocket science). I suggest you measure yours as well.

It's a simple fact that SATA is nowhere close to NVME in terms of performance, be it throughput or latency.

The most important reason to avoid SATA is to keep the computer case neat and clean, without extra cable management for data and power.

 

[mrbazmondo]

If you don't know what I'm talking about then why are you saying that its false?

On some motherbaords the m.2 is implemented as pcie lanes connected to the CPU. On others its implemented as secondary pcie lanes provided by the chipset - these are slower. I never said anything about SSD vs NVMe for latency.

 

[Le Samourai]

You'll possibly lose two sata ports if you add another M2. I've got two 960 EVOs with my maximus ix code board and I can only use two ports out of six.
Edit: Double-checked and it looks like I'm just losing two ports.

 

[Minstadave]

Just add a large SSD, wont notice any speed from the M.2 in real world usage.

Absolutely this, especially if you’re just dumping games on it. Only thing you’ll notice is the price.

 

[Minstadave]

I have no idea what you are talking about. I trust my numbers, measured on my own computer with my own SSDs. NVME has shown less than half of the latency of SATA (0.04ms vs 0.09 ms, no rocket science). I suggest you measure yours as well.

It's a simple fact that SATA is nowhere close to NVME in terms of performance, be it throughput or latency.

The most important reason to avoid SATA is to keep the computer case neat and clean, without extra cable management for data and power.

You’re taking at cross purposes. Mrbazmodo is talking about the difference between m2 drives connected via CPU lanes vs lanes off the chipset which are slower. You’re talking about m2 vs SATA.

 

[Deleted member 138126]

On some motherbaords the m.2 is implemented as pcie lanes connected to the CPU. On others its implemented as secondary pcie lanes provided by the chipset - these are slower. I never said anything about SSD vs NVMe for latency.

If your motherboard is one of those where the M.2 slots are hanging off the chipset rather than directly off the CPU, you can just buy a £20 PCIe card and put the M.2 drive in that. You probably can't boot off it, but for a secondary drive it's fine. Would be very interesting to see some benchmarks of all the various options.

 

[LeMson]

Buy another ssd and raid 0 it

 

[voidshatter]

On others its implemented as secondary pcie lanes provided by the chipset - these are slower.

Then why don't you ask which motherboard the OP has (if different from the one in his signature)?

 

[mrbazmondo]

Then why don't you ask which motherboard the OP has (if different from the one in his signature)?

Now you've learnt something new why didn't you?

Asus Z170M Plus spec page has m.2 listed under a chipset heading, so looks to be limited by its PCI lanes to 2GB/s, possibly less if there re other bottle necks.

 

[voidshatter]

Now you've learnt something new why didn't you?

Asus Z170M Plus spec page has m.2 listed under a chipset heading, so looks to be limited by its PCI lanes to 2GB/s, possibly less if there re other bottle necks.

Can't say we've learnt anything until you post benchmark numbers for the motherboard.

 

[mrbazmondo]

Can't say we've learnt anything until you post benchmark numbers for the motherboard.

You want me to post benchmark results for a board I don't own for your amusement? Go buy one yourself if your're that interested.