Is PCIe speed measured or hoped for ?

alan9182

Member
The last item on the Sensor Status report is
PCIe Link Speed 5.000 Gbps 5.000 Gbps 5.000 Gbps 5.000 Gbps

I hope this means my motherboard not only supports but is running as PCI Express Base 2.0 specification.

QUESTIONS :-
Do you actually measure this 5 Gbps as present reality, or do I have to risk modifying the BIOS to achieve this ?
Is there any possibility that this old motherboard is / was actually built to the previous PCIe 1.0 specification ?

The last published specification specification for my motherboard shows 2.0 is supported,
but I do not know if that was true of the initial production,
and a FAQ about a graphic card on my motherboard shows that
"M3A32-MVP Deluxe supports PCI-E 2.0. But PCI-E 2.0 support is disabled by default. "
http://www.asus.com/Motherboards/M3...nowledge_ECB22657-39D7-0171-2661-B0E802C46D52

I intend adding a PCIe USB3 card to drive a 5 Gbps USB3 External drive.
One company can offer a "small" card for an x1 socket and warned me it would give only half speed in my x16 socket,
and suggested a larger and more expensive card to support the full speed of the USB3.

I need to determine, preferably before I buy, whether the smaller and cheaper range of x1 PCIe cards will be adequate,
or whether that would waste half the speed to my HDD.

Regards
Alan
 
The value reported is the current PCIe transfer rate of the GPU, more precisely the negotiated PCIe speed between the PCI Express Root Port (controller) and the GPU. It's based on the actual status of the PCIe link.
For a more precise information about the PCI bus topology and features you might check the main HWiNFO window with a hardware list in a tree on left side (note that in case you're running it in Sensor-only mode, you'll need to disable this mode in order to see that window).
 
Thank you for the information, I see much more with that option unchecked.

I am puzzled by the following :-

You report
" Motherboard Slots: 2xPCI, 4xPCI Express x16"
Which agrees with
" Slot Designation: PCIEX16-1"
" Slot Designation: PCIEX16-2"
" Slot Designation: PCIEX16-3"
" Slot Designation: PCIEX16-4"
and all 4 slots have
" Slot Data Bus Width: 16x / x16"
and only the first in "in use"

I am disturbed by the fact that which I search for "PCI EXPRESS]"
you only report on three of the four slots with no absolute indication of which one is missing.
i.e.

ATI/AMD RD790 - External Graphics0 Port A ---------------------------------
MEDION Radeon HD 4670 -----------------------------------------------------
ATI/AMD RV730 - High Definition Audio Controller --------------------------
Those three promise
" [PCI Express]
Version: 2.0
Maximum Link Width: 16x
Current Link Width: 16x
Maximum Link Speed: 5.0 Gb/s
Current Link Speed: 5.0 Gb/s"

The above are followed by
"ATI/AMD RD790 - PCI Express Port A ----------------------------------------
[PCI Express]
Version: 2.0
Maximum Link Width: 2x
Current Link Width: 1x
Maximum Link Speed: 5.0 Gb/s
Current Link Speed: 2.5 Gb/s"

Please advise,
Is this 2x/1x my PCIEX16-4 slot with 3 quarters of the links missing ?
Is the current Link Speed something that I can fix by changing the relevant BIOS setting for that port ?
Do I have to restrict my choice of a USB3 card to a short x1 version ?

I am concerned that the only White x16 PCI Express slot that I can see is near the edge of the motherboard,
and I suspect there could be 3 more adjacent slots that are obscured from sight by Graphics and Adio cards,
so possible I do not have any hope of using a proper x16 slot.

Report attached as ZIP

Regards
Alan
 

Attachments

  • ALAN-DESKTOP.zip
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The main problem is, that it's not possible to determine the physical PCI Express/Slot topology using any software. There's simple no way how to retrieve such information from the system. So it's only possible to determine the logical topology of the system (how the links are divided between ports and devices) and that's what HWiNFO gives you.
The best way is always to check your mainboard manufacturer's manual.
The chipset on your mainboard supports a total of 42 PCI Express lanes, from which 6+4 are reserved for other devices (like your SATA and Ethernet controllers). So there are 32 lanes available for slots: x16 of them are utilized by your GPU, so you should have either x16 or 2* x8 available.

Exact placement should be described in the mainboard manual, for you model here:
http://www.asus.com/Motherboards/M3A32MVP_Deluxe/#support_Download_8
If you have a look at it, you'll see that if you want to use a single GPU + additional card, you have the following configuration available:
Slot1: x16
Slot2: x1
Slot3: x16
Slot4: x1
 
@Martin

Many thanks for that link.
I had been told that the PCI Express had White sockets, and all I could see was what your linked manual shows (on page 2-22) as a PCI Slot

I now realise that I have easy access to not only that slot, but also
Blue PCI EXPRESS x16_3 SLOT and
Black PCI EXPRESS x16_4 SLOT

May I assume that a board in Slot 4 with two USB3 ports will be restricted at "x1" to 2.5 Gbps when
Reading two files, one file from each USB3
Writing two files, one file to each USB3
Transfering one file from one USB3 to the other,
But when placed in Slot 3 at "x16" it can keep up to 16 USB3 ports fully occupied at 5 Gbps ?

Not that I expect to be buying 16 USB3 devices ;)

Regards
Alan


@ Cmp_Cmndo
Thanks for the caution (which is disappointing)

Regards
Alan
 
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