System crashed after New disc installation

[Miglanc]

Hi, I’m new on the forum. I have an iMac late 13, I replaced hard disc and memory. I installed new system mojave and keybord and moussee don’t work proper, system crashed. Can you help me?

 

[cmaier]

Hi, I’m new on the forum. I have an iMac late 13, I replaced hard disc and memory. I installed new system mojave and keybord and moussee don’t work proper, system crashed. Can you help me?

We’re going to need more information. How did it crash? What do you mean the keyboard and mouse don’t work? Did it boot? Did any error message appear?

 

[Miglanc]

Keybord and mouse are loosing connection with the computer. System froze, I can't do anything, I have to restart it and the same thing happens, no error appers

 

[MBAir2010]

unplug the mouse and keyboard, then restart the imac-

what happens?

 

[Miglanc]

I did it. The same situation. Connection is for a minute or two, I can open website and than everything freeze. Do you think that I installed disc or memory in a wrong way? Or maybe this New system mojave is not compatible with this hardware? Is it possible?

 

[KeesMacPro]

What brand and model drive did you install?
What brand,model and size RAM did you install , and did you remove the old RAM or added the new RAM ?
In about this Mac does it show all RAM sticks installed?
How long does it take for the iMac to boot?

 

[MBAir2010]

Mojave would not boot if the OSX was not compatible.
can you be more specific to let us how much your iMac starts
example is: were you see the taskbar, and can use the internet or a program like "pages"
you probably need a quick PRAM reset.

 

[Fishrrman]

If it's a 27" iMac (with easily changed RAM), the TAKE THE NEW RAM OUT and put the OLD RAM back in.

Does that make a difference?
It's very likely that it WILL.

 

[Miglanc]

Ok so I can see the new 16gb RAM. And I tried to install Catalina booting from external harddrive. In a half way id instalation computer restarts and starts booting again and again. I don’t know what to do.

 

[Miglanc]

If it's a 27" iMac (with easily changed RAM), the TAKE THE NEW RAM OUT and put the OLD RAM back in.

Does that make a difference?
It's very likely that it WILL.

This 21.5” iMac. And I can see the New RAM.

 

[Miglanc]

Mojave would not boot if the OSX was not compatible.
can you be more specific to let us how much your iMac starts
example is: were you see the taskbar, and can use the internet or a program like "pages"
you probably need a quick PRAM reset.

Do you think that the problem can be becouse I have a system on an external mini SD card?

 

[MBAir2010]

most likely, is a "external mini SD card" something that can fit into a camera?
if so yes! they do not have anything powering someone that needs power.
do you have a time machine back up for the iMac?
i would reinstall that and then upgrade to Mojave or later

I understand getting the best OSX for an older mac being important
for me I Have a MacBook air 2010 running mojave, el cap runs better, but won't read an iPad.

 

[Fishrrman]

OP wrote:
"Do you think that the problem can be becouse I have a system on an external mini SD card?"

In my experience, Catalina and Big Sur WILL NOT INSTALL onto USB flash drives, so they probably won't install onto SD cards, either. I can't answer for Mojave, never tried installing it to a USB flash drive.

You probably need a REAL EXTERNAL DRIVE on which to install, such as:
- an external USB3 SSD
or
- an external USB platter-based hard drive.

Get rid of the SD card, get an actual "hard drive", and start over.