So if I have inside 750W? there is no reason to change? a model is unknown ... something in Chinese written on it.
is stable at 300MHz, 325 goes to idle mode and orange light blinking. the temperature is not more than 48 degrees. it is the power supply or something else? I connected directly to PC because my TP-link internal router not working
Move out PSU from case.
I run my avalon with external PSU at 336 with 750 stock PSU (Enermax ENM750EWT-S RG) and it never restarts.
Tested @354 but noise level unacceptable, 750w PSU easily handle moderately overclocked units.
if problem still occurs than check you "cgminer api log"
It must be something like that (my unit @336 2 days w/o restart):
[no_matching_work] => 0
[match_work_count1] => 20069
[match_work_count2] => 20320
[match_work_count3] => 20197
[match_work_count4] => 19944
[match_work_count5] => 20103
[match_work_count6] => 19962
[match_work_count7] => 19976
[match_work_count8] => 20163
[match_work_count9] => 20064
[match_work_count10] => 19961
[match_work_count11] => 20056
[match_work_count12] => 20235
[match_work_count13] => 20173
[match_work_count14] => 20481
[match_work_count15] => 20215
[match_work_count16] => 20042
[match_work_count17] => 20044
[match_work_count18] => 19992
[match_work_count19] => 20040
[match_work_count20] => 20398
[match_work_count21] => 19627
[match_work_count22] => 19978
[match_work_count23] => 20354
[match_work_count24] => 20186
All counters have almost same values. (~5% diffs) if not you have defective modules or some module overheated (usually second module w/o temp sensor ).
And you can try to reset your router, may be it's not dead.
https://bitcointalksearch.org/topic/m.2672023
even had help view team viewer from someone who has solo setup and for some reason it just would not work on my computer 
