I paid $62 for one, and $69 for the other (back in 2020). I mistakenly bought the first one without eMMC, but made sure the second one I ordered had it.
Now they are selling an LTS version for a mildly better price. However the LTS has 26 pins for GPIO rather than 40 pins. You can choose between 3G and 4G of ram and you can choose whether or not to get 16G of eMMC.
In December of 2021, I no longer see these available. You can buy the "RockPi 4B" for $100 these days, this adds the "AI" chip for additional cost, which is not something I want, but on the other hand it should not get in the way either.
I see a note from "Larisa" at Orange Pi (in April of 2021) that says:
OPI 4 is not discontinued. It is because of its tight supply of raw materials. Each time the material is only 500-1000PCS. Basically, when the production is completed, it has already been booked by domestic customers. So AliExpress and Amazon have not been online for a long time.If you need it, you can contact me. I am the sales of Orange Pi factory.
The A72 cores can run up to 2.0 Ghz, and the A53 at up to 1.5 Ghz. That is the claimed specification anyway. I read about people being happy to run the big cores at 1.6 and the small at 1.4.
I am also reading the claim that "Clock for clock, A72 is 2-4x faster than A53". The A53 is a strict in-order execution core. It would be an interesting study to learn more about A72 versus A53.
The whole big/little core thing ends up being pretty funny since linux does not differentiate between the six cores!
There are other things as well that are not of immediate interest to me. There is a 24 pin PCIe connector, and a connector for a camera, as well as audio.
It gets power from a coaxial connector (5 volts, 3 amps). It does have a USB-C connector, and given that USB-C can supply 3 amps of 5 volts, it just might work to power it that way.
I am fretting over the need for a heat sink, the RK3399 does seem to get plenty hot. I placed an order for two nice metal boxes that serve as heat sink, made by Orange Pi themselves and selling for $10 which is a decent price.
Tom's electronics pages / tom@mmto.org