Change ASUS MMO to Gen 3 PCIe instead of Gen 4
Change ASUS MMO to Gen 3 PCIe instead of Gen 4
I possess an ASUS ROG Strix Z590-E gaming Wi-Fi motherboard and I’m attempting to connect a 2.5-inch SSD. My processor is a 10th generation Intel CPU, so I understand I can’t use the 4th generation model. I also recall that the first slot only supports 11th generation CPUs, which seems odd but I’ll go with it. I’m hoping to utilize the second and third slots if possible, since the fourth slot is shared with my graphics card and will operate at 8x speed. I have a 3090 and haven’t spent much money just to keep it running at 8x instead of 16x. Realistically, 8x performance isn’t too bad, but when you invest around $1800 in a GPU (with a 25% tariff in ‘Mercia gotta love it), I want every frame to be smooth. I reached out to ASUS customer support online and they simply advised using the third and fourth slots for the 10th generation CPU, but can I somehow make the second slot work with a 3rd generation chip? It feels unreasonable that half my slots won’t function if I can’t use the 4th and need a BIOS fix. I understand the physical connections must be there from the CPU through the motherboard, but if it supports Gen 4, why not Gen 3? Edit: A few people mentioned that PCIe standards claim Gen 4 should be backward compatible with Gen 3, so plugging it in should work on Gen 3 if Gen 4 isn’t available. This isn’t true even though it should be. There’s no BIOS setting to change the PCIe generation for the first two slots—only to switch them to SATA or NVMe. I tested both drives in all slots, and they never appear in the first two regardless of BIOS adjustments, but they show up right after swapping them to the third and fourth slots. I’m frustrated because at the moment, ASUS can’t explain why and has left my request pending for a while despite promising a response within 48 hours. I’m considering telling them to replace the motherboard since it should work without using the third and fourth slots, which would waste half the GPU bandwidth. Plus, I have three M.2 drives and really don’t want to risk damaging my 10th generation CPU by spending another $500+ on an 11th generation one just to fit the slots on the board. Updated: November 17, 2021 – EdanMaus95
That's what I thought, though I've seen some discussions online where others faced issues. Since I'm out of state, I'll attempt it again once I return.
I’m currently speaking with ASUS to get their perspective. I checked the PCIe standards, which are uniformly set by a group known as the SIG (Special Interest Group). More than 900 companies support this, so it should be reliable in either direction. Curious to see their stance.
After speaking with ASUS again, the representative mentioned he couldn’t find a method in the manual or internal system to switch from Gen 4 to Gen 3 manually in BIOS. I’ve been moved up to a higher support tier. I plan to attempt a straight plug-and-play setup when I’m back home, but I remain doubtful since some users reported issues with my specific motherboard and CPU.
I understand many users face problems with Gen3/4 regarding risers, but simply connecting the card usually resolves the issue.