Adding a second M.2 to Asus ROG Strix b450-f

funkyouup

Hoping someone here can clear up some confusion, i was hoping to add another 1tb m.2 to my pc.

In the manual it states -

M.2_2 supports PCIE 3.0 x4 M Key design and type 2242/2260/2280/22110 storage devices

M.2_2 socket shares bandwidth with PCIE x16. When M.2_2 slot runs in PCIE mode, the

PCIE x16_1 slot will run at x8 mode.

I have a graphics card in PCIE x16 slot 1. Can or should I just move it to the secondary PCIE slot?

My CPU is an AMD Ryzen 7 3700x

minitrue

You could move the gpu but you shouldn't as that second slot will only do pci-e 3.0 x4 so it would be worse (and the 3rd one is pci-e 2.0 x4).

dotsman

Afraid not. According to the Tech spec, your PCIe options are

2 x PCIe 3.0/2.0 x16 (x16 or x8/x4)

This means that the second slot only runs at x4 (and the first drops down to x8 if you use the the second PCIe slot). Basically, you have 20 lanes. You are currently using all of them (16 for the graphics card and 4 for the SSD). If you require any more, then the first PCIe slot drops to 8 lanes to free up available lanes.

Your choices are either run the new SSD at SATA speeds or drop the graphics card to x8. The difference between x16 and x8 for the graphics card depends on your graphics cards. Unless it is a recent, high-end card, chances are the difference will be negligible. Even for recent high-end cards, it will depend on the game, resolution & settings, and even then it is not a drastic difference.

ED E

Doesnt he have 24 lanes? 16 consumed + consumed + 4 spare?

funkyouup

https://www.boards.ie/discussion/comment/118217902#Comment_118217902

The graphics card is a Asus GeForce GTX 1660 SUPER Dual EVO OC 6144MB GDDR6.

I don't really have a need to upgrade in the near future for my usage.

Edit/ should i just get a regular ssd and plug it in a sata port?

dotsman

https://www.boards.ie/discussion/comment/118217945#Comment_118217945

4 are going to the chipset. That's my understanding of that board (I hate how manufacturers describe PCIe lanes!)

https://www.boards.ie/discussion/comment/118218274#Comment_118218274

I cannot imagine any noticeable drop in performance by running a 1660 Super on 8 lanes.

You can just get a 2.5 inch SATA SSD. However, you could always just get the M.2 form factor and run it on SATA. That way, at least the drive has future value (recent and future chipset/motherboards have more lanes and M.2 slots etc).

But I think you are absolutely fine running it on PCIe. Best bet is to buy the M2 version. Take a quick benchmark of your most demanding 2-3 games. Put in the SSD, knocking your PCIe x16 down to 8 lanes and run the benchmarks again. If there is a noticeable difference, run the SSD as SATA for now. If not, enjoy the benefits of NVMe.

funkyouup

Thanks, think ill go with an m.2.