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Not getting gigabit Internet on AC5300 (Merlin) - Enable Hardware Flow Acceleration (Level 2) ?

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MKANET

Regular Contributor
I recently upgraded to a 1000Mbps Internet connection. To my surprise, my PC's are not getting any more than around 350Mbps.

However, I am able to do SMB file transfers between both PC's at >900Mbps... as fast as my Ethernet cards can handle.

Also, I can get full speed internet by bypassing my Asus router (Merlin Version: 384.13) .

I've been searching for a solution when I stumbled on the below thread:
https://www.snbforums.com/threads/enabling-hardware-flow-acceleration-level-2-in-ac87u.26886/

It seems like there may be a weird issue related to NAT Acceleration. Currently, I have NAT Acceleration set to "Auto".. however, only getting CTF (Cut Through Forwarding) is enabled in yellow text. My understanding from the above thread is that I need to have Flow Acceleration (Level 2) enabled to take advantage of 1Gbps Internet speed.

Could someone please confirm this is the cause of my slowness issue? I can't find any other explanation. If it is the cause... what's the best way to fix this issue. In that thread, it says I need to do the following:

- disabled QoS
- disable STP
- disabled HW Acc.
--> self reboot
- Enabled HW Acc.
--> self reboot

However, that didn't work for me. One person suggested in that thread to do "a complete NVRAM reset". I am willing to do this, however, I want to be sure that this will be the best chance I have at fixing my slow Internet connection.
 
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NAT acceleration on Auto does the Gigaspeed job. So that cannot be the cause.

So it might be in the configuration as from the information above I derive it is not in the cabling. My 5 cents: start all over and update to a later firmware version.

Member L&LD has already summarized for you how to do that in a proper way (M&M config & Nuclear Reset). https://www.snbforums.com/members/l-ld.24423/#info

Another of my 5 cents: take the 384.18alpha firmware of 29 May 2020. It is rock solid on both my AC5300's (don't be spooked by it being an Alpha version).

If you decide to go ahead with the Alpha: flash the firmware and do a Nuclear Reset and once you have done that execute the M&M config as described by L&LD.

Make sure you have your router completely configured before you start running scripts or other tweaks. Other line of thought: Who needs QOS with Gigaspeed?

On a closing note: if during the proces you cannot access the GUI execute a WPS NVRAM erase. Asus has changed something in the later firmware that causes this no access but the WPS NVRAM erase solves that once and for all.
 
possibly QOS enabled - I have ax88u, when I enable QOS my speed is 350-400 MBit when QOS disabled then 950 MBit ...
 
Modem could possibly have issues with router too. When I had an intel PUMA based modem, Qualcomm based wifi chips (R7800) seemed to work way better for WIFI consistency with my 400mbps plan.

Switching to a broadcom DOCSIS 3.1 modem, my GT-AC2900 seems to be much more consistent now.

A lot of combo designs or gateways (modem + Wifi) also follow this trend from what I can see. Not claiming this to be an issue for you, but just something I noticed.
 
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Thank you @SheikhSheikha for taking the time to help me out. Now I know that NAT acceleration on Auto is good enough. I'm already using firmware 384.17. Unless there's a huge benefit to using 384.18alpha over 384.17... I'll probably just keep this firmware for now.

My current settings are almost identical to L&LD's M&M config; since I also like to disable features I don't use.

I'll just have to bite the bullet and redo everything on my router with the presumption that there's something messed up in my configuration adversely affecting WAN->LAN bandwidth specifically. I just hope that the issue isn't some kind of obscure hardware issue that a full NVRAM reset wouldn't help.

I'm actually pretty excited about getting 1Gbps download speed. It will be nice to not have to wait for over an hour to download AAA game titles from Steam/Epic; and, also save a lot of time downloading TV shows/Movies from Netflix for offline playback. I agree, not very many people "need" Gig speed.

NAT acceleration on Auto does the Gigaspeed job. So that cannot be the cause.

So it might be in the configuration as from the information above I derive it is not in the cabling. My 5 cents: start all over and update to a later firmware version.

Member L&LD has already summarized for you how to do that in a proper way (M&M config & Nuclear Reset). https://www.snbforums.com/members/l-ld.24423/#info

Another of my 5 cents: take the 384.18alpha firmware of 29 May 2020. It is rock solid on both my AC5300's (don't be spooked by it being an Alpha version).

If you decide to go ahead with the Alpha: flash the firmware and do a Nuclear Reset and once you have done that execute the M&M config as described by L&LD.

Make sure you have your router completely configured before you start running scripts or other tweaks. Other line of thought: Who needs QOS with Gigaspeed?

On a closing note: if during the proces you cannot access the GUI execute a WPS NVRAM erase. Asus has changed something in the later firmware that causes this no access but the WPS NVRAM erase solves that once and for all.
 
Thanks for the tip. I had actually tried that. Unfortunately, it didnt make any difference.

possibly QOS enabled - I have ax88u, when I enable QOS my speed is 350-400 MBit when QOS disabled then 950 MBit ...
 
Just would add to the above that just having the settings as suggested in the M&M Config isn't enough if you haven't performed a full/proper reset on the router in a while.

This issue is a great example of a 'bug/glitch' that suggests to me the firmware is confused internally.

A proper reset will get the router back to a good/known state by giving the router the defaults it expects to see and work with.
 
UPDATE: I don't know if this makes any difference to my case but... It looks like one of my PC's DOES have 1Gbps download speed. My other PC is still stuck at 350Mbps download speed though. However, it still can do SMB file transfers at 1Gbps, but not Internet downloads.
 
Does a reboot of that PC help?
 
Unfortunately No. I even tried a full power-reset of both the router and that PC. I also booted that PC with Linux, still the same speed for Internet download.

Manually set the adapter to Gb, make sure various options aren't preventing you from Gb speed.
Sometime ago I had a few systems that wouldn't play well unless I set them manually.
 
The NIC already connects negotiates a 1GB/Full duplex connection automatically on that PC, otherwise, the PC wouldn't be able to receive SMB file transfers at 1Gbps. I did explicitly set the NIC to 1GB/Full duplex, but it didn't make any difference. Thanks though.

Manually set the adapter to Gb, make sure various options aren't preventing you from Gb speed.
Sometime ago I had a few systems that wouldn't play well unless I set them manually.
 
Thank you @SheikhSheikha for taking the time to help me out. Now I know that NAT acceleration on Auto is good enough. I'm already using firmware 384.17. Unless there's a huge benefit to using 384.18alpha over 384.17... I'll probably just keep this firmware for now.

My current settings are almost identical to L&LD's M&M config; since I also like to disable features I don't use.

I'll just have to bite the bullet and redo everything on my router with the presumption that there's something messed up in my configuration adversely affecting WAN->LAN bandwidth specifically. I just hope that the issue isn't some kind of obscure hardware issue that a full NVRAM reset wouldn't help.

I'm actually pretty excited about getting 1Gbps download speed. It will be nice to not have to wait for over an hour to download AAA game titles from Steam/Epic; and, also save a lot of time downloading TV shows/Movies from Netflix for offline playback. I agree, not very many people "need" Gig speed.

I wrote: who needs QOS with Gigaspeed. That is something else than needing Gigaspeed. In fact, internet speed is never fast enought :-D
 
Try an nic driver update see if that helps.
 

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