Modem: HG659b

Hello. I am getting periodic internet connection problems...

im going to a website (slow).. it works, & then sudenly it not working (error below)...  i refresh the page & the website is now working.

Ive got a fast internet - 40Mbps in peak times & 100+ in off-peak times when I use speedtest.net  However when im not using speedtest, everything is very slow...

I use OPERA browser (latest version)...  its the only browser that i can play Forge of empires on.  (none of the other browsers like that game).

Anyway, back to my error :-

This site can’t be reached

The webpage at https://en.wikipedia.org/wiki/Cat might be temporarily down or it may have moved permanently to a new web address.

(this happens on a dozen / more  major websites - & small websites too - no pattern).

i refresh the page & it brings it up..

ANYWAY - back to rambing..   ive googled a bit, & found something about proxy servers. https://customers.trustedproxies.com/knowledgebase.php?action=displayarticle&id=40  Though i dont think that is the cause of my problems...

Spark modem: HG659b

i am wondering - is there a DNs / PROXY / or other settings that i can use to allow my Pc to connect nicely with spark.

my DNS settings are curently set to Google :- IPv4: 8.8.8.8 and/or 8.8.4.4. (IPv6 turned off)