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PCIe 5.0
- Thread starter Rtjr
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Yes, put it in a compatible USB enclosure or Thunderbolt enclosure (probably will be commercialized soon).
The logicboard and CPU of iMac 2019 can only support PCIe 3.0, anyway.
Yes.
I mean that all the hardwards inside iMac 2019 can only support PCIe 3.0 and older devices, including the GPU.
PCIe 4.0 nVME SSDs are backward compatible, which means they will function like an PCIe 3.0 device inside iMac 2019.
If you want to utilize the PCIe 4.0 or later protocol, you will need external devices that support.
Thanks for the reply. I am about to change the Fusion Drive out with a new nvme ssd and also change the hdd to a ssd. Will changing out the gpu make this computer up to date? PCI’s 5.0 is out now. Would that work in my computer if I changed the gpu or the cpu also?
You would have to change out the supporting chipset, too.
Other than that mod (highly unlikely to ever happen), the 2019 iMac does not support PCIe 4, let alone PCIe 5.
As mentioned above, PCIe 4 should clock down to PCIe 3. I suppose PCIe 5 will also clock down, but unknown for sure.
(The chipset/bus does not magically upgrade to PCIe 5, just because you plug a newer device into a socket... You get PCIe 3, as that is what the chipset (and the logic board) is designed to support.
You won't get anywhere close to the advertised speed on a PCIe 5 device.
Other than that mod (highly unlikely to ever happen), the 2019 iMac does not support PCIe 4, let alone PCIe 5.
As mentioned above, PCIe 4 should clock down to PCIe 3. I suppose PCIe 5 will also clock down, but unknown for sure.
(The chipset/bus does not magically upgrade to PCIe 5, just because you plug a newer device into a socket... You get PCIe 3, as that is what the chipset (and the logic board) is designed to support.
You won't get anywhere close to the advertised speed on a PCIe 5 device.
A good result for TB3 is 2800MB/s R/W.
That is because of the 40Gb/s TB3 data rate only about 22Gb/s is available for PCIe 3 data transfer.
The rest is reserved for DisplayPort video and various encoding losses.
You generally got better results with Mac OS using an NVMe SSD with DRAM to hold the data allocation database.
More recent SSDs tend to use other methods.
That is because of the 40Gb/s TB3 data rate only about 22Gb/s is available for PCIe 3 data transfer.
The rest is reserved for DisplayPort video and various encoding losses.
You generally got better results with Mac OS using an NVMe SSD with DRAM to hold the data allocation database.
More recent SSDs tend to use other methods.
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