My Mac Pro 4,1 (flashed to a 5,1) that I just purchased yesterday has a Radeon HD 4870 was glitching so I grabbed my old gtx 660ti and plopped it into the bottom slot and booted it and no post so then I put both cards in and the Radeon had 4870 had a display but not the 660ti when I plugged in a monitor it did nothing. The primary operating system that I use is mac os Mojave and it didn't show any display so I got out my snow leopard HDD. And went to the system profiler and it shows up as display type: GPU but it doesn't show any picture when connected to another monitor.
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MP 1,1-5,1 Mac Pro 2009 4,1 (flashed to 5,1) Gtx 660ti not showing display but shows up in system profiler as a gpu.
- Thread starter anick1122
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GTX 660Ti is a Kepler GPU supported with the Apple made native NVIDIA graphics drivers from 10.8.2 to the most recent BigSur release. It's GK104 based and basically a weakened GTX 680.
No need to get webdrivers for a GTX 660Ti unless is the GPU have unusual PCIe id.
Btw, you GPU could be defective or your Mojave install is problematic, try a clean High Sierra install to eliminate any doubts, where you can even get NVIDIA webdrivers installed.
No need to get webdrivers for a GTX 660Ti unless is the GPU have unusual PCIe id.
Btw, you GPU could be defective or your Mojave install is problematic, try a clean High Sierra install to eliminate any doubts, where you can even get NVIDIA webdrivers installed.
Now my usb installer 10.13.6 just has a big O with a dash down the middle of it and my screen went to 1440x900 instead of 1920x1080
Do you have a known working Mac that you can install High Sierra to a disk and then move the disk to your eraly-2009 Mac Pro?
Besides GPU problems, your new to you Mac Pro could also have BootROM problems, a very common issue with cross-flashed early-2009 Mac Pros.
Besides GPU problems, your new to you Mac Pro could also have BootROM problems, a very common issue with cross-flashed early-2009 Mac Pros.
The O slashed screen is to indicate that what you are trying to run is not allowed, prohibited. Could be an incorrectly created createinstallmedia installer, for example.
You don't even know if the Mac Pro works correctly and trying to get it going with two GPUs will not gonna make it easier, borrow a sure known working AppleOEM GPU like Nvidia GT120 or ATI HD 5770 and then try again.
You don't even know if the Mac Pro works correctly and trying to get it going with two GPUs will not gonna make it easier, borrow a sure known working AppleOEM GPU like Nvidia GT120 or ATI HD 5770 and then try again.
First, you told that the HD 4870 is glitching, second you are not even powering this GPU, a GPU that requires two PCIe 6-pin power connections.
Borrow a GT120, no power cables required, then you can debug your GTX 660Ti.
I don’t have anyone that just has a gt120 and I don’t want to buy one. Do you think the fiber card is doing something? Or was My Mac just flashed incorrectly? And the 4870 gpu had the 2 6 pin pci connectors in it until around 5 minutes before I took the picture.
Create a bootable installer for macOS - Apple Support
You can use a USB flash drive or other secondary volume as a startup disk from which to install the Mac operating system.
