Dell XPS 15 SSD NVMe slow after July 2016 firmware update and throttled CPU (Core i7)

Did you ever figure this out? I've got a Lenovo Thinkpad X1 Carbon with the same disk (thnsn5512gpu7) and I get the same<ADMIN NOTE: Profanity removed as per TOU>poor write speed. Read is great though. The PC is brand new, and this is not what I expect.

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roll back to the previous BIOS - I don't trust version A10 after it made the screen flicker worse, which the update was supposed to fix. Wont be surprised if its 'broken' other things.

I never benched my SSD after the update when I had it installed but I have now since rolled back and performance is super fast on my 1TB PM951.

@Paal: not yet :( @Simba: unfortunately, for my current service tag, the only BIOS available on dell.com is XPS_9550_1.2.10.exe released on July 5. As for the Intel Rapid Storage Technology Driver, same thing: the only version available is Serial-ATA_Driver_6K2TK_WN32_14.5.2.1088_A00.EXE released on Oct 25, 2015. There is no "Older version available" for the above 2. Not sure how to roll back then.

Hi nickfall,

you wont find the previous bios versions in your service tag my account drivers download page. Its the same for everyone with the XPS 9550.

The BIOS isn't configuration specific but model specific so BIOS for 9550 applies to all 9550 users.

Good news is you can get it from here, roll back to A06:http://downloads.dell.com/published/pages/xps-15-9550-laptop.html

pretty much all the latest and previous releases can be had from there.

The rapid storage technology driver is the earliest release it seems given by the A00 revision. There is however a later release of this which is 14.8.9.1053.

Iv filtered the page for XPS 9550 so should take you straight there. Hope this has been helpful.

@Paal: not yet :(

@Simba: unfortunately, for my current service tag, the only BIOS available on dell.com is XPS_9550_1.2.10.exe released on July 5.

As for the Intel Rapid Storage Technology Driver, same thing: the only version available is Serial-ATA_Driver_6K2TK_WN32_14.5.2.1088_A00.EXE released on Oct 25, 2015.

There is no "Older version available" for the above 2. Not sure how to roll back then.

Thank you Simba, great tip. I will try this in the afternoon and update the thread after that.

Will keep the Intel Rapid Storage version I have as it is for now. 

Reverted to the older BIOS - still poor 4K read times... leading to poor performance in IDE (Eclipse) or browsers (Chrome) for instance.

I remember that on the same day, Windows pushed the Windows 10 Anniversary update. Could it be correlated to that? Any update from other people impacted by this issue?

Since I'm having this issue on a Lenovo and not a Dell it might not be totally relevant, but mine is running Enterprise edition and IT at work has deferred the aniversity update for now. So I atleast experience this on the "plain" windows version.

Another update: I ran CPU-Z, and the numbers are even worse. It looks like the CPU is throttled. I googled around, tried disabled SpeedStep, made sure the Power options do not set up CPU caps, etc. to no avail.

So it seems there is a multitude of problems here: slow-ish SSD, coupled with a throttled down i7 :(

No idea what to do at this point.

DIsabling speedstep WILL throttle the CPU (it'll run as if on battery all the time).

To further help anyone with this disk. Found out that Toshiba har rebranded this as OCZ RD400/400A and that both firmware utility and NVMe drivers are available to download here: http://ocz.com/eu/download/

Installed both the SSD utility, that claims the firmware is up to date, and the NMVe driver. But still I don't get even close to expected performance.

I did re-enable SpeedStep, to no avail. Also re-tried the default BIOS settings. See screenshots of CPU-Z. The core speed is stuck on 800 Mhz, no matter the workload put on the CPU. Any possibility to set the speed of a core manually?

have you double checked your power profile settings? for example the pci express power management settings and the cpu state settings? turn off the power management options and make sure the processor states have not been capped for min and max settings.

Found out thatToshiba has rebranded this drive as OCZ RD400/400A and that both firmware utility and NVMe drivers are available to download here: http://ocz.com/eu/download/

Installed both the SSD utility that claims the firmware is up to date. Also installed the NMVe driver. But still I don't get even close to expected performance.

Read more about the drive here: http://www.tomshardware.com/reviews/toshiba-xg3-ssd-ocz-revodrive-400,4434.html

(Toshiba bought OCZ back in 2014 and apparently some drives are sold under the Toshiba name and some as OCZ).

I did re-enable SpeedStep, to no avail. Also re-tried the default BIOS settings.

See screenshots of CPU-Z. The core speed is stuck on 800 Mhz, no matter the workload put on the CPU.

Any possibility to set the speed of a core manually?