I haven't tried this yet
The old bootloader is there 'cause of the ch34x. You can flash the new bootloader to these boards, but the connection while flashing is unstable.
But, i think that won't work
How i do that
An Uno is an Uno and it always has the new bootloader; unless the manufacturer screwed it up and programmed it as a Nano with old bootloader. Because an Uno has the new bootloader, there is also no "old bootloader" option for the Uno (only for the Nano).
- Does COM2 (or COM3) disappear from the IDE (and from Windows device manager) if you disconnect the board.
- Any yellow triangles in Windows device manager?
- Did you indeed install the driver?
- When you press and release the reset button, do you get a couple of quick flashes (not the 1 second on/off sequence) after the release? This will indicate if the bootloader is functioning.
- Does the board give you the 1 second on/of sequence? This will indicate if the board was programmed at the factory with the blink sketch.
- It's normal for boards with CH34x to show "unknown device".
- What is the history of the board? Is it new and never worked? Or did it work in the past.
- What is all connected to the board? If anything, disconnect it all and tell us the project that you're working on when it started to fail.
It worked for a while then I restarted my computer and it stopped working. But all the "information" matches what happens to me
Well, let's see what comes up - we are talking about a "clone" here, not the original. 115200 baud is new bootloader, 57600 is the old one. There are old charges of CH34x that do not work will with 115200 baud high throughput rates -> the vendors that place these components also flash the old bootloader (or the new one with patched baudrate).
I found that the partition style is mbr, how do I configure ide
before i Format my PC It was GPT not MBR
This is normal and expected for your board. Arduino IDE's Tools > Board Info actually provides information about the port you have selected from the Tools > Port menu. Some boards produce a serial port that has identification properties that are unique to that specific board model. This allows Arduino IDE to identify which board model produced that port. In this case, you will see the name of the board model in the "BN" field of the "Board Info" dialog. For example, here you can see it when I have selected the port of my genuine Arduino UNO R4 Minima board:
But your cheap Chinese UNO R3 derivative board uses the general purpose WCH CH340 USB to serial bridge chip. This chip does not produce any properties that are unique to the board model. There is no way for Arduino IDE to know which board that CH340 chip happens to be on (or even whether it is an Arduino board at all), so it is not able to identify the board model of the selected port. For this reason, it shows "Unknown" in the "BN" field of the "Board Info" property:
But you don't need to worry about that. Arduino IDE's port identification is only a convenience feature. You can still use the boards that produce a port that is not identifiable without any problem. You just need to take a bit more care to make sure to select the correct port from Arduino IDE's Tools > Port menu, since the port will not be labeled with the board name as would be the case with a board that produces an identifiable port.