[QUOTE=xpeca;11421] but with most current stock fw hitting router ping packet drops over 802.11 n roughly between 5-10%, even the router is located in the next room - signal strength ~ -55 dBm, no channel collisions in the nearest neighborhoods etc.[/QUOTE
Does it mean you only lost ping packets when the wireless mode is on 802.11N and channel width 40Mhz? How about the 11b/g/n mixed and 20Mhz?
Since there is no channel conflict with the neighborhood, you may give a try on the wireless mode and channel width.

Update from my side:

Tested Stock Firmware Version:
3.16.5 Build 130322 Rel.59120n


System Up Time:
6 days 00:16:36

Thats the longest i ever got on a stock firmware. Looks like its quite stable to me on stock so far.

New firmware up:
3.16.5 Build 130329 Rel.62825n

Best I've got so far is 2 days 20hrs.... :(

I'd be much more content having to reset maybe every 2 weeks, but not every 2 days!
I'm starting to feel this will never be sorted out! And it pains me to know that I got another one of these routers for a work colleague who wanted Wi-Fi at home.

Perhaps an automatic reboot option is necessary in the stock firmware as a last resort..

Casper,

Try the same build that i am using, Its up close to 13+days and this was the longest i ever got with any firmware/openwrt/stock/gargyole etc, I had the same problem thats described on this thread, Router is up and running, But Wifi stops responding after few days. Even got a replacement to see if its hardware. Finally after so much trouble the build i am using seems to do the magic.

Firmware Version:
3.16.5 Build 130322 Rel.59120n

Hardware Version:
WR740N v4 00000000

System Up Time:
13 days 21:44:20

Same BIG problems with 740N ver. 4.21. I haved problems with wireless -the router was totaly unusable with encryption...i tried everything - latest firm, channels, encryption, only B, only g, mixed ...Finaly фром the store gave me another 740N ver. 4.21 and LOL i finaly have working piece :) BUT... the wireless stopping working every 1-2 days. No internet, can`t ping the device...3.16.5 Build 130329 Rel.62825n is the firmware. Nothing helps just restart from button or power!

ps sorry for my broken english

All those who are investigating this, does the connection start working again if instead of rebooting the router you switch the WiFi on your laptop on and off? My router is in another room, and this seems to work for me. Ok, not a solution to the problem, but might shed some more light.

Nope! Only restart of the router helps me. But i changed dhcp lease time to 2880 and its workin little better /the router loosing wifi connection sometimes 10-15 times per day and the pc reconnects automaticly without need to restart the router/ I notice that i have ping losses to the router! This is the second item 740n for which i pay and not working correctly! Shame..

I noticed that the problem occurs when are connected more than ONE pcs! With ONE connected station no problem! ??? I changed firmware with OPENWRT and its working perfectly! Buggy tp-link firmware. Never mind- Never again tp-link router!

I am back to where we started. After the above updates. now my router misbehaves again. Wifi stops responding, worst cases cant even be online for 8hrs or so. Its the same firmware and config that i got 11+days up. maybe heat ? I did update to latest firmware again. Will keep testing.

I am kind of fed of this stupid device. Might have to get a differnt hardware sooner, This time wont look at tp-link.

I'm back on ddwrt r19519 which usually kept the wifi working a bit longer but still caused issues after a while, but now I have had it up and running for 18 days 6hrs already.
Granted it's not the same router I was using, but it is still the WR740n v4.23. And official firmware was still giving problems with wifi, so essentially, it should be problematic...but it's not (thus far).

UPDATE: It continued working for 27 days, but then I went away for a week so I turned it off, but it was still working.
Back up again now, so let's see if it gets even further.