The Pi 4 has been released, found wanting, redesigned, and re-released (in typical Raspberry fashion). And finally I have my hands on one. So, do I think it's any good?
Well, yes and no.
First impressions
The Pi 4 is certainly a big step up from the Pi 3. I have the 4GB version (because reasons), and that really does make things fly compared to the Pi 3. USB 3 and Gigabit Ethernet are certainly a big bonus. My main reason for wanting a Pi 4 is as a desktop replacement (my desktop is a power hungry beast and I'd like something a little less costly to run). I have a triple-head setup at the moment, but could take a hit down to dual head, and the Pi 4's dual HDMI outputs would certainly fit that bill.
In practical usage
Out of the box the Pi 4 is still slow. Yes, it's fast when it comes to moving stuff around in memory, but the fact that it's still based on aged and slow SD card technology means that it's really got a massive bottleneck on filesystem accesses. Even with a high speed expensive SD card it's still slow. But thanks to USB 3 it's possible to connect an external SSD, which certainly speeds things up. But of course that adds more expense and bulk to an otherwise lightweight and low cost system.
My biggest initial bugbear though is the operating system. The Raspberry Pi foundation are lazy. Plain and simple. They tout the Pi 4 (and the Pi 3 for that matter) as being a blistering fast V8A 64-bit ARM system. It's one of the major selling points in all the literature. Yet they can't be bothered to build an operating system for it. The only version of Raspbian* is built for the 32-bit V7L, so feature wise you may as well just be using a Pi 2. You don't get any of the extra facilities that the V8A core gives you. You don't get 64-bit processing. In short, it's a waste of space having a 64-bit processor with enhanced instructions. You gain absolutely no benefit from it.
And why do they not create a 64-bit V8A version of Raspbian? Because it would be "too much effort" to maintain two versions of the OS.
If that's not a kick in the balls to their dedicated users I don't know what is.
And then I got a second HDMI cable to set up dual head, and that's when my impressions of the Pi 4 really plummeted.
While the first HDMI port works perfectly out of the box, the second doesn't. Or at least not for me, and not for many other people. The second port just doesn't seem to like many normal computer monitors. After much fighting I managed to get it to acknowledge that there was actually a monitor attached, but even then all I could get out of it was red fuzz. I guess it might work if I used the exact same monitors that Raspberry tested it with, but that's not how things are in the real world. If you're going to sell something as having a feature, and making that feature one of the big selling points, at least have the courtesy to make that feature work.
And now a comment on the power situation: It's far more hungry than the Pi 3. You need a 3A power supply, and (less well known) a suitable cable to connect it with. And then it's only just barely able to operate. Even with a beefy USB PSU and a good cable I was having voltage issues when connecting an externally powered SSD to USB. I ended up creating my own power system which directly interfaces to the 5V pins of the GPIO header before I could get it to remain stable. The simple fact that the documentation states that the USB C connector isn't actually compatible with the standards should ring alarm bells. I mean, come on - how hard is it to put a standard USB power management chip on there?
My final impression
It can be summed up in one word: "Meh".
While the Pi 4 is certainly an improvement over the Pi 3 it's still sadly lacking in many respects - most of them completely inexcusable. And to bring it up to a specification and speed where it's beginning to be usable as a desktop computer you need to be prepared to spend at least as much again on extra hardware and create a Frankenstein's monster of a setup. The broken second HDMI is a real killer in my opinion. If it works for you then you're one of the lucky ones. Maybe you can get it going by tweaking some of the configuration options, but not for me (configuration options that really shouldn't even need to exist!).
Much of the slowness could have been mitigated by providing a proper disk interface. Maybe an M2 SSD socket, or an actual SATA connector would improve things. USB 3 is good, but not convenient since you need external adaptors.
Summary
Pros
- Faster than the Pi 3
- Has USB 3
- It's cheap
Cons
- You only get crippled 32-bit operation*
- SD is still slow, you need an external SSD in real world operation
- The power supply situation is pitiful
- Dual head is hit and miss
- It gets hot. If you don't have good ventilation you'll want a fan
- Still lacks proper storage connectivity
*Ubuntu now do a 64-bit Raspberry Pi 4 image. Hurrah!