comments:
Mistral-Fien posted on r/thinkpad1w
It won't work Optane is a PCIe SSD (aka NVMe), while the T440p has SATA signals in the WWAN slot. The T440p doesn't even have an Expresscard slot you can't use an Expresscard to M.2 NVMe adapter. AFAIK the only free PCIe signals are on the WiFi slot (which has a BIOS whitelist you need to remove) and the solder pads for the nVidia GPU. :O You need an M.2 SATA 2242 SSD like this.