Originally Posted by bluefire529
"...the TX-RZ840’s heat-sink gains black anodised paint that improves cooling efficiencies and reduces thermal distortion"
Not sure if it's something that they changed on later builds of the RZ830, but the 830 I have definitely has a black anodized heatsink. (Open Box (actually new), $480 several months ago.)
Also noticed Onkyo intl site page features the cooling fan over the heatsink, but the USA site doesn't mention it. (Haven't seen it turn on though, hasn't gotten hot enough to trigger it.)
I saw a note that the 840 is getting a firmware update for IMax Enhanced (so is the 920) but not the 830 apparently.
(Also saw the note on the 840's improved HDMI board/traces, etc, and they tout a Quad-core processor in the 840.)
I'd rather have an 840 of course, but still very happy with this RZ830 performance for the price. (Driving 7.1.2 - Klipsch RF-83s, RC-64, RS-62s, RS-41s - all crossed at 80hz except the RF-83s at 60Hz, RS-41s at 100Hz), PC-13 subwoofer. (I may add a small amp later to power the rears, to allow for 2 rear heights.) I had a NR3007 (55lbs) years ago, replaced by a RX3050 (less power but nice features), but this current setup has never sounded better. (Detailed and very tactile with lots of punch in this small/sealed room.)
Excuse the off-topic post, just wanted to note that at least some 830s have a black anodized heatsink.