PCIe Gen 4 vs 5 question

[NickKz]

I have an HP Z2 Mini G9

 

It uses a W680 chipset but for whatever reason on this device HP does not give you any PCIe Gen 5 enabled lanes at all

 

Both M.2 slots are Gen4x4 and the GPU riser is Gen4x8 (x16 mechanical).

 

First question is why would HP do this?  Is there some kind of significant cost or component upgrade fee on their end to enable Gen5 support?  What specifically “enables” gen5 pcie lanes on W680?

 

Second question is, is there any benefit at all to running two Gen5 drives in RAID1 like the newer Crucial gen5 t700, over two of the gen4 t500 drives in the same raid1 config?

 

Might as well also ask about the heatsinks…these SSD mfgs seem to charge quite a bit extra for the heatsink equipped versions.  

I’m guessing probably a better idea to just get a third party heatsink and buy the bare versions?

[ki8aras]

4 minutes ago, NickKz said:

I have an HP Z2 Mini G9

 

It uses a W680 chipset but for whatever reason on this device HP does not give you any PCIe Gen 5 enabled lanes at all

 

Both M.2 slots are Gen4x4 and the GPU riser is Gen4x8 (x16 mechanical).

 

First question is why would HP do this?  Is there some kind of significant cost or component upgrade fee on their end to enable Gen5 support?  What specifically “enables” gen5 pcie lanes on W680?

 

Second question is, is there any benefit at all to running two Gen5 drives in RAID1 like the newer Crucial gen5 t700, over two of the gen4 t500 drives in the same raid1 config?

about the second question, on paper there is a difference, but other than very specific applications the extra speed provided by gen5 isnt needed

[GuiltySpark_]

3 minutes ago, NickKz said:

Is there some kind of significant cost or component upgrade fee on their end to enable Gen5 support?

Yes, the tolerances of the traces and possible need for re-drivers can drive the cost up quite a bit. 

 

That being said in a system like that there is almost zero need for Gen5 SSD's altogether. Frankly I'd argue there is zero need for them at all in a desktop system. 

[jaslion]

Do you nees the speed of the drives?

 

Like can you actually consistently 100% the drives for your usecase?

 

If not then you dont need faster storage at all.

 

As for why hp did that. Money, makes you wanna get the new one that has it.

 

 

You bought the cheap one so they take features away that only the too expensive ones have.

 

However pcie 5.0 traces do cost more to manufactur so it is possibly a mix of both

[NickKz]

1 hour ago, jaslion said:

Do you nees the speed of the drives?

 

Like can you actually consistently 100% the drives for your usecase?

 

If not then you dont need faster storage at all.

 

As for why hp did that. Money, makes you wanna get the new one that has it.

 

 

You bought the cheap one so they take features away that only the too expensive ones have.

 

However pcie 5.0 traces do cost more to manufactur so it is possibly a mix of both

From the reviews I have read it seems like the random read and write as well as the IOPs are around the same as the previous gen4 (with these crucial specifically), but with large block sequential R&W is where the improvement is.  So, the answer is —- maybe  

It also looks like the Phison controller is better in the gen5 drives, but produces more heat.  The integrated heatsink version of the drive is HUGE!  So big that it won’t even fit in my case, lol.  So I guess for now the decision has been made for me. 
 

I think I’m going to return them and get the t500 instead.

[Eigenvektor]

46 minutes ago, NickKz said:

So, the answer is —- maybe

That's a huge maybe. Do you have a use case that benefits from 7 GB/s (Gen4), let alone 14 GB/s (Gen5) or even 28 GB/s? (assuming RAID could actually achieve that without running into a bottleneck elsewhere first)

 

Even with 40 Gbps network you'd be limited to around 5 GB/s, so unless you do a ton of large file transfers between equally fast disks, there's very little need for that speed.