PCIe Whitelist in Proprietary PC's ?

[Bint Box]

Hi,

Would anyone please be able to provide any feedback about some PC vendors using a whitelist embedded into their PC's that validates if a PCIe card is acceptable?
A colleague bought a couple of older HP desktop PC's and no matter what they tried they could not get some PCIe cards to be recognised in the expansion slots.

The PCIe cards were DVB cards and known to be working from testing in other PC's, some of which were older generation than the proprietary PC's with the PCIe recognition issue.
Additionally, the BIOS was checked out to make sure there was no disabling or wrong speed allocated to the PCIe slots. In fact, the cards were x1 cards which would run at any PCIe speed setting.

After a bit of googling and arguing with the seller it was discovered there might be an HP whitelist in play, blocking recognition of the DVB PCIe cards?

Has anyone come across this before and is there a fix for it?
Thank you for any feedback.


Rgds
Bintos

 

[Armageus]

I've come across it in Laptops (Lenovo especially), with only certain Wifi cards and the like being Whitelisted, but not come across it in desktop PCs (and especially not HP).
In some of the smaller Form Factor HP and Dell PCs though, there has been a power limit applied to the PCIE 16x slots (25w, 35w or 50w rather than the normal 75w).

What model PC are you using?

 

[Bint Box]

I've come across it in Laptops (Lenovo especially), with only certain Wifi cards and the like being Whitelisted, but not come across it in desktop PCs (and especially not HP).
In some of the smaller Form Factor HP and Dell PCs though, there has been a power limit applied to the PCIE 16x slots (25w, 35w or 50w rather than the normal 75w).

What model PC are you using?

The two PC's with the issue are both HP 4th generation with an i5-4590 CPU.
I think they are HP Elitedesk 800 G1 models as they are mid tower, I am not sure if the CPU equivalent Prodesk models were all SFF.
If the HP 4th generation Prodesk range came in mid tower size then there is a possibility they could be Prodesk and not Elitedesk?

Both PC's have the same issue of not recognising the DVB cards yet they do recognise NVIDA GPU cards in the same slots so it is not a damaged slot?

 

[Armageus]

The two PC's with the issue are both HP 4th generation with an i5-4590 CPU.
I think they are HP Elitedesk 800 G1 models as they are mid tower, I am not sure if the CPU equivalent Prodesk models were all SFF.
If the HP 4th generation Prodesk range came in mid tower size then there is a possibility they could be Prodesk and not Elitedesk?

Both PC's have the same issue of not recognising the DVB cards yet they do recognise NVIDA GPU cards in the same slots so it is not a damaged slot?

We've had 800G1 Mini Towers, and 800G2 SFF at work and not had any problems with random PCI-E cards (e.g. off brand Serial and Parallel cards, USB cards, and non-HP network cards), so I don't think it's a whitelist issue.

As per page 14 of the Quickspecs though - it may be the PCI-E slots not supplying enough power

https://www.hp.com/hpinfo/newsroom/press_kits/2013/HPDiscoverBarcelona/HP_EliteDesk800G1_Desktop_Mini_QuickSpecs.pdf

Even on the TWR model, the PCI-E 1x slots are listed as only supplying 10W max power - according to Wikipedia this is correct, however Wikipedia also mentions

"A full-sized x1 card may draw up to the 25 W limits after initialization and software configuration as a high-power device."

Which could be the issue, as I seem to recall DVB, especially DVB-S cards being quite power hungry, so might be that the HP BIOS simply doesn't allow cards to negotiate to this high-power 25W state.

PCI Express - Wikipedia

en.wikipedia.org

Difficult to find any information on the Slot Power supported on a Prodesk 600 G1, but I'd imagine they are similarly limited (if not worse being a lower end model)

 

[Bint Box]

...

As per page 14 of the Quickspecs though - it may be the PCI-E slots not supplying enough power

https://www.hp.com/hpinfo/newsroom/press_kits/2013/HPDiscoverBarcelona/HP_EliteDesk800G1_Desktop_Mini_QuickSpecs.pdf

Even on the TWR model, the PCI-E 1x slots are listed as only supplying 10W max power - according to Wikipedia this is correct, ...

Thank you for taking the time to reply with what seems the most likely explanation.
The DVB cards are specified as drawing a max of 15W, if the slot is limited to 10W, the card probably cannot draw enough power to operate?

 

[Orcvader]

Is there a CSM option in the BIOS? Could try enabling that and see if that does anything too.

 

[Bint Box]

I'm back, this time with the same issue in a Dell Precision 3620 workstation

The Dell has a 290W PSU and an NVIDA GT1030 with max power draw of either 20W (SDDR4) or 30W (GDDR5) is recognised and works in the pCIe slots.
However, the DVB card with max power draw of 19.2W in the same slots is not recognised.

The DVB card max power draw is less than the GT1030 which seems to indicate it is not a power limiting issue to the PCIe slots?
The same DVB card works perfectly well in another machine with an ASUS motherboard.

 

[Armageus]

The Dell has a 290W PSU and an NVIDA GT1030 with max power draw of either 20W (SDDR4) or 30W (GDDR5) is recognised and works in the pCIe slots.
However, the DVB card with max power draw of 19.2W in the same slots is not recognised.

The DVB card max power draw is less than the GT1030 which seems to indicate it is not a power limiting issue to the PCIe slots?

A GT1030 is a PCI-E 16x card though, and is allowed 66W (75W after configuration).

PCI-E 1x cards will still only be allowed 10W in a PCI-E 16x unless they configure as a high-power device (25W)



Edit:
According to the Dell Precision Tower 3620, 3420 Technical Guidebook (Page 17), there are a few limitations on PCI-E card power that aren't really standard. E.g. Slot 4 is a PCIe x16 slot but is only rated for 25W, but can exceed that as long as the combined load for slot 1 and slot 4 is less than 100W

Dell Precision Tower 3000 3620, 3420 Technical Guidebook | Manualzz

Get the technical guidebook for the Dell Precision Tower 3000 series workstations, models 3620 and 3420. Explore detailed specifications, features, and configurations for these powerful work platforms.

manualzz.com

 

[Bint Box]

A GT1030 is a PCI-E 16x card though, and is allowed 66W (75W after configuration).

PCI-E 1x cards will still only be allowed 10W in a PCI-E 16x unless they configure as a high-power device (25W)



Edit:
According to the Dell Precision Tower 3620, 3420 Technical Guidebook (Page 17), there are a few limitations on PCI-E card power that aren't really standard. E.g. Slot 4 is a PCIe x16 slot but is only rated for 25W, but can exceed that as long as the combined load for slot 1 and slot 4 is less than 100W

Dell Precision Tower 3000 3620, 3420 Technical Guidebook | Manualzz

Get the technical guidebook for the Dell Precision Tower 3000 series workstations, models 3620 and 3420. Explore detailed specifications, features, and configurations for these powerful work platforms.

manualzz.com

Thank you for the link and the comments.

The power draw according to NVIDIA for the GT1030 is a max of 30W.
Even if it were up to 75W the total power draw of slot 1 with the GT1030 and slot 4 with the DVB card is less than 100W so meet the Engineering specification.
Additionally, if I use the internal graphics from the board with the GT1030 removed from the ststem the DVB card is still not recognised and it is the only device populating a PCIe slot.

I have subsequently tested another DVB card in the same machine and it is recognised.
This seems to indicate it is a conflict with specific DVB cards and the Precision 3620 board rather than a power issue with the PCIe slots.
I know the DVB card with the recognition issue is OK as it is recognised in other non proprietary PC's, some of which are quite a few generations older than the Precision 3620 model.

Oh well, some insight, on to the next....

 

[Armageus]

Additionally, if I use the internal graphics from the board with the GT1030 removed from the ststem the DVB card is still not recognised and it is the only device populating a PCIe slot.

If the Dell BIOS isn't allowing it to negotiate as a Full-Power device, it will be limited to 10W regardless of which slot it's in or any other devices.

Non-proprietary PCs have less BIOS limitations as they are normally just an "off the shelf" BIOS image. HP/Dell etc customise the BIOS to fit the actual hardware, e.g. limiting maximum power draw and the like to fit the PSU/Chassis requirements.

 

[Bint Box]

If the Dell BIOS isn't allowing it to negotiate as a Full-Power device, it will be limited to 10W regardless of which slot it's in or any other devices.

Non-proprietary PCs have less BIOS limitations as they are normally just an "off the shelf" BIOS image. HP/Dell etc customise the BIOS to fit the actual hardware, e.g. limiting maximum power draw and the like to fit the PSU/Chassis requirements.

Unfortunately, there are no BIOS settings I can find that allow editing PCIe power status.
The only option is PCIe slots enabled or disabled en bloc, not even individual addressing of slots.

If the slot was limited to 10W then I would have thought that the other DVB card that I tested would also not have been recognised?
This card that was recognised has a 15W power draw, in excess of the 10W limitation.
It could be a selective 10W limitation I suppose, dependent on the device but both the recognised and unrecognised DVB cards are from the same manufacturer.