MP 1,1-5,1 problems with crashing Mac Pro 3,1 (early 2008), need help solving

[chasg]

A followup: the SSD plugged into the second TB port of the Terramaster enclosure spontaneously dismounts, but only very occasionally. Not good.

 

[TommyBen1]

I am having a similar problem with my 3,1 with a bit of a twist. Here is my story. First boot doesnet make it to the boot screen before shutting down and fans a blazing. Turn off and reboot again. Makes ot to the boot screen and to the password login. Shuts down and fans are blazing. After about 4 to 5 times of doing this the system will stay up for quite awhile.I have installed an ATI Radeon 4870, new power supply. Checked the ram with no issues. Any thoughts

 

[Macschrauber]

I am having a similar problem with my 3,1 with a bit of a twist. Here is my story. First boot doesnet make it to the boot screen before shutting down and fans a blazing. Turn off and reboot again. Makes ot to the boot screen and to the password login. Shuts down and fans are blazing. After about 4 to 5 times of doing this the system will stay up for quite awhile.I have installed an ATI Radeon 4870, new power supply. Checked the ram with no issues. Any thoughts

replace the 4870 for a test run