Hello there @Ausdauersportler,
below I'm adding some info.
I don't know (u r right) why the old vBIOS said 1GB...
Actually, with the stock Dell vBIOS, the graphic card is seen as "AMD Radeon R9 M380 2 GB" by native High Sierra and oclp/Monterey.
About the heatsink, I already grinded and thoroughly tested mine. There's no thermal or electrical issue at all. The temperatures are perfectly under control by sensors and - mainly - I usually don't play games nor stress the GPU. I just went from double check for loose connections of board components and for accidental contact with the heat sink. All is ok and perfectly insulated. As I said before, thermal paste MX6 was recently applied on GPU and K5-PRO on DRAM and other components close to heatsink. I don't think the temperatures are the issue here.
Could it be the (maybe undersized 'cause of its age) power supply?
Amyway, with your last vBIOS my card is correctly detected as ATI Radeon FirePro M6100 2GB. Few seconds, or couple of minutes, from the start, my iMac freezes and reboots. Endlessly.
Do you need any other details or tests from me?
I'm sadly stuck, so just ask or point me at the right direction.
Thanks again for your patience and support.
T.
below I'm adding some info.
I don't know (u r right) why the old vBIOS said 1GB...
Actually, with the stock Dell vBIOS, the graphic card is seen as "AMD Radeon R9 M380 2 GB" by native High Sierra and oclp/Monterey.
About the heatsink, I already grinded and thoroughly tested mine. There's no thermal or electrical issue at all. The temperatures are perfectly under control by sensors and - mainly - I usually don't play games nor stress the GPU. I just went from double check for loose connections of board components and for accidental contact with the heat sink. All is ok and perfectly insulated. As I said before, thermal paste MX6 was recently applied on GPU and K5-PRO on DRAM and other components close to heatsink. I don't think the temperatures are the issue here.
Could it be the (maybe undersized 'cause of its age) power supply?
Amyway, with your last vBIOS my card is correctly detected as ATI Radeon FirePro M6100 2GB. Few seconds, or couple of minutes, from the start, my iMac freezes and reboots. Endlessly.
Do you need any other details or tests from me?
I'm sadly stuck, so just ask or point me at the right direction.
Thanks again for your patience and support.
T.