RT-AC66U limits wired speed to 55mbps down despite cable upgrade to 100mbps down...

[Mako88]

Strange one, have used my AC66U and kept the firmware updated for two years now and always had good speed that matched my cable internet package (55mbps down).

Just upgraded to 100mbps down however, and tested the speed connected from the cable modem directly to the PC and it hit 100mbps easily. The problem is that when I put my AC66U back in the loop it caps out (wired) to the PC at 55mbps...

I tried a few different firmwares just now to see if anything clicked, the latest from merlin, asus themselves, etc, all the same, hard speed cap of 55mbps.

Not using QoS or really anything exotic, any ideas?

 

[Mako88]

UPDATE: Just tested the wireless 5.0GHz via a few devices in the house for kicks and they hit 95mbps down, 12mbps up, which is where it should be.

So it's something in the way the wired WAN communicates with my PC that's throttling it to a max of 55-59mbps. The PC is Win 7, X99 MB, nothing obviously set wrong and the gaming LAN is wide open on the board. Not sure what I can test, maybe something in the board's BIOS?

 

[PolarBear]

I think this is unlikely to be a generalised problem. I am also using an RT-AC66U and to a wired PC I'm getting 75Mb/s down and 7Mb/s up, as advertised by the ISP.

(Using Merlin 378.50, more or less default settings but with everything to do with IPv6 switched off, uptime 74 days.)

 

[Mako88]

I managed to isolate the issue, it was the lame Killer E2200 NIC in my MSI X99 board. That nonsense marketing tripe company's driver was throttling the bandwidth. Replaced it with the matching Qualcomm chip driver, and voila, full 98mbps down and 15mbps up now.

All good.