I used to live in Canada, and I've been to Ottawa a few times.
If you have a Canadian Tire nearby, that'd be the first place I'd check.
I'm looking at those fan specs again:
You have a YS tech, and I suggested a Sunon.
YSTech:
RPM: 2'800
Noise: 45 dB
max CFM: 125
max pressure: 7.6mm (H2O)
Sunon:
RPM: 2400
Noise: 35.5 dB
max CFM: 69
max pressure: 0.17 inches H2O (4.23 mm)
So although it would be quieter, it would probably perform worse.
Sunon spec (Oops, sorry, I don't do other people's homework!
)
What temp difference do you see, from running the fan at 7 volts, versus 12v?
I think you should try a bigger/better fan first (maybe you've got something around the house you can try?). Did you get around to putting a shroud around the BIX?
If you could try a REALLY powerfull fan, you'd see for yourself what we mean about the BIX. Alternatively, your YS tech fan can be overvolted to 16 Volts (see specs).
BTW, I have the same case (Chieftec Dragon DA-01). I'll be putting my rad where the PSU goes, so I'll have a 6 by 8 opening, for (possibly) an old 68' vette core. I plan to use a blower as a fan, pulling air from the side, and blowing out the back. Once one starts using auto parts...