Are you sure they don't boot? Something in the way you need to set up your HDMI changed, the video mode I had set on my B didn't work on my 3B so I got a blank screen. Watch your LEDs, if they're flickering it's booting. I had a post on it at https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=146684&p=966321#p966321 I was able to boot into 640x480 mode once I edited my /boot/config.txt on a different machine.
There are only 2 Raspbian images in their download area, one with X, Mathematica, Libre Office, the works, and a "Lite" image with no X. They still support all models with those images. And they've sold over 8 million of them. I don't think I use big enough numbers to need 64 bit really, it's more appealing to load 8 characters at once. I'm not planning a Mars mission. If I can't fsck a 1 TB drive that's a problem. freebie# calc '2^32' 4294967296 freebie# calc '2^64' 18446744073709551616 On 7/28/16, Lennart Sorensen <lsore...@csclub.uwaterloo.ca> wrote: > On Thu, Jul 28, 2016 at 12:22:23PM -0400, Alan Corey wrote: >> Huh? I thought they claimed they were interchangeable. I had an >> image from my model B days 3 years ago that I booted on my 3B. And I >> cloned a working current 3B SD card and booted a Zero from it. There >> isn't a different Debian image for every brand of motherboard and CPU, >> they probe to see what hardware is there. I wouldn't expect older >> images to contain drivers for newer hardware maybe. >> >> I guess I wouldn't make too much of the jump to 64 bit just yet. I >> remember when i386 jumped to 32 bit. 16 bit had a messy segmented >> memory addressing scheme I was glad to get away from. I can't afford >> more than 32 bits worth of RAM anyway, especially since I've usually >> got about 4 machines running. > > Well it isn't actually just a question of memory (most 8bit CPUs had 16 > bit address space, and many 16 bit CPUs had 24 or 32 bit address space, > and some 32 bit x86 and arm chips can do 36 or 40 bit address space > physically). What you often gain going to a 64 bit CPU is the ability > to do 64 bit arithmetic in one instruction, and store the variables > in one register rather than two, rather than a bunch of stuff the > compiler generates for you. After all if you take two 64 bit integrs > and try to multiply them on a 32 bit CPU, most of the time you end up > with numerous multiply, shift, add, mask, instructions to implement > the calculation using 32 bit only instructions, while on a 64 bit CPU > usually it is just one instruction. So the 64 bit CPU will probably do > the calculation faster than the 32 bit CPU. Of course if you only need > 32 bit calculations, then it doesn't matter, so in many cases it isn't an > issue, but when it matters it can really make a difference in performance. > > -- > Len Sorensen > -- Credit is the root of all evil. - AB1JX