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HP Recommended
Model #: 700-216
Microsoft Windows 8.1 (64-bit)

I wanted to upgrade my Spectrum internet speed from 100 Mbps to 400Mbps.. A new modem was supplied, and I replaced my router with a 1Gbps capable unit, but I find the Atheros AR8131 PCI-E Gigabit Ethernet Controller will only run at 1 Gbps when there is no router plugged into the circuit from modem to computer. It remains at 100Mbps. Speed tests confirm a difference in actual speed.

I noted several other users of that Atheros model reported the same problem years ago, with the only resolution being finalized at changing from CAT5 cables to CAT5e cables. Well Ive been using a 5e cable from the start, so thats not the answer

I did see an increase in actual speed when the router was taken out of the circuit- from 75 Up/ 12 Down to 204 Up /24 Down

Why is having a router in use preventing ethernet controller from allowing its maximum speeds ? How do I fix thsi?

No driver update was recommended when I did an update search, and no more recent driver is available from HP, though other sites report newer version for Windows 8.1

HP Recommended

@MedicMomSI Welcome to HP Community!


I understand that the Atheros AR8161 PCI-E Gigabit Ethernet Controller will not run at 1 Gbs.


There are lots of issues with getting GigE to work including but not limited to:


  1. Poor quality cables  (use a known good cat 5e or cat 6 cable)
  2. Excessive length (over 100 meters) or short Ethernet cables (under 1 meter)
  3. Speed negotiation with AUTO fails (fix the speed to 1 Gig full duplex with both devices)
  4. Router or modem hardware issues (check the specifications)
  5. The on board adapter is not robust enough to support GigE a speeds that are anywhere close to GigE.

I would recommend you upgrade your cable to cat 5e/6 at least.

Sometimes it's the auto negotiation that is detecting a lower spec'ed cable & defaulting to 10/100.

"Category 5 enhanced cabling, also known as Cat5e, is an improvement on Cat5 cabling. It was made to support 1000 Mbps "gigabit" speeds, so in theory, it's faster than Cat5. It it also cuts down on crosstalk, the interference you can sometimes get between wires inside the cable."

To go beyond, 100Mbps, both ports should be able to support Gigabit Ethernet.
The Qualcomm Atheros ar8161 PCI-E card fullfills this criteria.
As you managed to achieved 250 Mbps download speed before I'm going to assume that the router is able to support that too.

If the cable route fails, I would suggest to reinstall the drivers for the PCI-E Ethernet card.


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