m.2 PCIe doesn't run at x4

[JohnB15]

I installed an SSD to my PC but it runs about twice slower than it is supposed to.

It seems the cause is a PCIe link width. It should be x4 as it stated in the motherboard (Erica2 8643, B550 chipset) and the SSD specs. HWiNFO64 reports that Maximum Link Width is x4 but Current Link Width is x2. I have tried two different models of SSDs: HP EX950 and Sabrent Rocket 4.0 with the same results.

It looks like the issue is at the motherboard side. BIOS version is F.11.

Any idea how to fix it?

Thanks

[Grzwacz]

Greetings,

Welcome back to the forum.

I am not a HP employee.

I have seen this issue on some predecessor 500 series and 600 series HP consumer PCs.

HP is limiting M.2 data to two PCIe lanes instead of four lanes.

Did you check the BIOS for a setting to bump up to X4? No BIOS setting may mean you are locked at X2.

The latest BIOS is F.11 Rev. A (Link).

Regards

[Daniel2908]

The bad thing is, that HP every writes x4 for the slot and nowhere is notived that they limit it to x2.

There is no setting in bios. 

[JohnB15]

So HP publishes fake specifications? That is interesting. 

It would be good to know what HP Legal Department is thinking about such actions?

[Daniel2908]

In my opinion, yes.   Ands the worst is that there is no one from HP and so on who is caring about it for months. No BIOS Update for this, nothing. 

[Daniel2908]

Really bad that no one from HP dirctly is looking here forward to give an answer. 

[Daniel2908]

@JohnB15: Did you find a solution to get 4 lanes? Or did you sell the computer? 🙂

[JohnB15]

With Gen4 SSD it provides 3.5GB/s that is an acceptable speed. Next time I would not buy a prebuilt PC. It is better to assemble it by yourself. Less stresses 🙂

[Daniel2908]

It's good to know which ones did you buy? In the meantime, I am writing everywhere on the Internet and at online shops for these HP devices that they only run with 2 lanes. It annoys me that HP writes x4 everywhere  and does nothing about it. I really hope that my bad reviews everywhere will decrease their selling. 

[Grzwacz]

Hi,

Is this really a problem in everyday use?

I can't tell the difference between a SATA SSD versus a PCIe SSD in normal use.

Benchmarks can drive you up the wall. Faster read/write speeds do affect specific applications but normal, everyday use does not apply.

This issue is not a deal breaker when using a PC.

The M.2 socket is capable of providing four PCIe lanes to the socket (no law suit there). HP has limited data throughput to two PCIe lanes. Motherboard manufacturers can do whatever they want.

Regards