For those of you craving to read the follow-up to 'Deleauvive back to his good ol' N64 to please his young bro' & sis'', here it is :
I went back to the retro-shop
today (nice address, not lost among the other big console shops), the guy acknowledged the 1080 Snowboarding cartridge he sold me had a problem, and he changed it. I bought Mario 64 & Yoshi's Story from him, also.
It seems that blowing warm air from the mouth gives a kick to a failing cartridge (well, no need to go as far as to kissing it, thankfully), so I blew like crazy on the back of those 25 cartridges I told you about. They all worked, but the minute I switched to another, the TV screen went black again. Oh, and before I forget, I use an Allsop solute to clean the connectors with an ear-tip (avoid using alcohol or syndets).
Anyway, I found that approximately 20% of the cartridges were working almost flawlessly (which is not so bad considering their origin) without that blowing stuff. So the console had nothing to do with it, as you may have guessed. Also, the few games I bought from the shop worked fine, since their yellow plastic connectors were not nearly as damaged as those from our living room shoe box.
I need to have both the controller & the rumble pack checked at the shop, but this is happy ending, even if it cost me a few bucks. If someone told me I'd buy second-hand N64 games in 2008, I would have wet my pants laughing