Slow PCIe M.2 speed on asus p8z68-v gen3

[Boldur20]

I'm experiencing slow speed on Samsung 960 EVO 250 GB.

Read speed of 700 MB/s is only fraction of normal speed.

My GPU is connected to PCIe slot 3.0 x16_1

Asus hyper m.2 x4 card is plugged in PCIe slot 2.0 x16_3 which as according to the manual is only compatible with pcie x1 and x4 devices.

I have tried connecting it to slot 5 (gray) at x8 speed but 960 show up in windows, still it can't be accessed.

I've updated to latest bios version v3802 from 2015/04/07 (P8Z68-V PRO/GEN3 bios worked)

PCIe 2.0 16_3 at x4 mode is only capable of 700 MB/s.

Maybe the motherboard is to old for extreme m.2 speed?

My primary mobo is sent for repair (X99 Deluxe) speed on that was 2100 MB/s +/-

 

[USAFRet]

Yes, your motherboard and available slots is slowing things down with that drive.

 

[marksavio]

yes most of the older asus boards limits the actual PCIE gen3.0 speeds based on the CPU type you have. your board is a Z68. so i wouldnt expect maximum performance on it if its lesser than probably a 2600K chip. this was the early days of PCIE 3.0

 

[Boldur20]

So PCIe 3.0_2 at X8 can't be used to yield higher speed?

 

[USAFRet]

So PCIe 3.0_2 at X8 can't be used to yield higher speed?

"only compatible with pcie x1 and x4 devices"

If it needs an adapter like that, you will almost never get the best performance.
That board was released long before PCIe drives were. It was never designed for them.

 

[Calvin7]

The Samsung 960 EVO features PCIe Gen. 3.0 via the NVMe 1.2 protocol.

Asus has no plans to provide NVMe support for legacy Intel Series 6 Chipset motherboards such as the P8Z68 GEN 3.

You would need some third-party modified BIOS or software such as Clover for NVMe support.
https://www.win-raid.com/t2375f46-Guide-NVMe-boot-without-modding-your-UEFI-BIOS-Clover-EFI-bootloader-method.html

 

[Boldur20]

Bios 3802 update did something good -> doubled read speed. Better than nothing

 

[alpha27]

if I remem correctly a 2600k only had support for pci-express version 2 so u will lose 1 third performance = around 2000mbps from the evo, which is pretty darn quick!