x99x Killer M.2 PCIe question...

jimgravina wrote: OR...is it true if you have the M.2 connected directly to the M.2 slot itself.

^^ Is true.




"" **If M.2 PCI Express module is installed, PCIE5 slot will be disabled.""

That means if an M.2 is inserted in the motherboard mounted Ultra M.2 slot then PCIe5 will be unavailable.




HTH

jimgravina wrote: Hey all, Curious about something with my M.2 port and PCIe 5 slot.  I have the ASROCK x99x Fatality Killer 3.0 board and the manual states that if a M.2 PCIe is used, then the PCIe 5 slot will be disabled.   Is this true only for a PCIe based M.2?  In other words, if the M.2 was connected to a card in which you then add to a PCIe slot.  OR...is it true if you have the M.2 connected directly to the M.2 slot itself.   Im asking because I need to use the PCIe 5 slot to add the ASROCK thunderbolt add in card and thats the only open slot I have left and need to know if they M.2 drive is gonna screw me... Thank you! Jim

I'm confused by what your configuration is. Multiple scenarios are possible, and two flavors of M.2 SSDs, PCIe and SATA.

Are you using an adapter card, M.2 to PCIe slot adapter, which is inserted in a PCIe slot for an M.2 PCIe SSD?

If that is correct, then the PCIE5 slot will still be available.

If you have an M.2 PCIe SSD connected to the Ultra M.2 slot itself, then the PCIE5 slot will not be available. The PCIe lanes are shared between the M.2 slot and PCIE5 slot. You can use one or the other, but not both.

But it sounds like you might have a SATA M.2 SSD, is that true? If so, and the specs are confusing about this, it seems you will NOT lose the PCIE5 slot. Instead, you lose the SATA3_2 port.

What M.2 SSD are you using?

jimgravina wrote:

What device(s) were you testing connected to the Thunderbolt card?

jimgravina wrote: It's the new Weatern Digital My Book Pro 6TB external drive which is set up in RAID 0. It has both USB 3.0 and Thunderbolt 2. Yes...it's faster than the USB connection, but not by much. I used the supplied thunderbolt cBke that came with the hard drive. USB 3.0 was giving me roughly 330mb/s and 287mb/s write. Thunderbolt was giving me 320mb/s read and 300 mb/s write. Tested with both crystal disk and black magic disk speed test. Crystal disk was giving me slightly lower speeds. Reviews on this drive was showing upwards of 400mb/s over thunderbolt. I know it's not an allles to apples comparison but thought I would be a little closer to that than I am.

The speeds of that drive can be affected by many things. Reviews test drives under the best circumstances usually, for example the drive will be new and empty, so it will perform at its best. An HDDs speed varies depending upon where the data is stored on its platters, the inner tracks are slower than the outer tracks. If the HDD has been used for a while, it may need a good defragment to keep its data together, more contiguous as it is called.

CPU power saving options cause reduced IO performance, as well as the Windows Power Plan being used.

Since the benchmark results of both interfaces are so close, my guess is the drive itself is the limiting factor. If any HDD could perform at 400MB/s, that would be a miracle, but I assume that is in RAID 0.

USB does not use the same interface to the drive that SATA does, so cannot use the AHCI protocol, which helps SATA perform better. I don't know what the internal interface between the drive and the Thunderbolt connection is for the external drive, it might be the same packet type interface of USB.