Power saver mode in newer nvidia cards

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1

I recently got a new rtx 5080. (well, it was new to me). It’s a PCIe gen 5 card.
My Motherboard has a PCIe gen 5 slot slot for the video card.

..so far so good, but then I run this…

Code:

Every 5.0s: sudo lspci -vv -s 01:00.0 | grep -E 'LnkCap|LnkSta'

and I get this

type or paste code here

                LnkCap: Port #0, Speed 32GT/s, Width x16, ASPM L1, Exit Latency L1 unlimited
                LnkSta: Speed 2.5GT/s (downgraded), Width x16
                LnkCap2: Supported Link Speeds: 2.5-32GT/s, Crosslink- Retimer+ 2Retimers+ DRS-
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete+ EqualizationPhase1+

Huh? what? Speed 2.5GT/s, that’s terriible, that’s worse than my old radeon, so I go through my UEFI settings
update my drivers, etc… and run the test again, same results.. make no sense.

But its seems the newer nvidia cards have a power saver mode, when not under load. So I run glmark2.
(it could be any GPU stress app). and run that same command in another terminal.

Code:

Every 5.0s: sudo lspci -vv -s 01:00.0 | grep -E 'LnkCap|LnkSta'                                                                                                

                LnkCap: Port #0, Speed 32GT/s, Width x16, ASPM L1, Exit Latency L1 unlimited
                LnkSta: Speed 32GT/s, Width x16
                LnkCap2: Supported Link Speeds: 2.5-32GT/s, Crosslink- Retimer+ 2Retimers+ DRS-
                LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete+ EqualizationPhase1+

Ahhh… much better. 32GT/s, but that only happens when under a load high enough to put it out of power saver mode.

2

Right, this is the case at least as far back as the 3000 series.

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