# item.guide
Side-by-Side Comparison SSD

M.2 vs. PCIe AIC

Comparing 2 standards across 8 specifications. 8 key differences identified.

Comparing:
M.2
PCIe AIC

M.2 is the dominant SSD form factor today, sized by a code like 2280 (22mm wide, 80mm long). B-key supports SATA or PCIe x2; M-key supports full PCIe x4 NVMe speed; B+M-key dual-notch modules are actually capped at PCIe x2, not the full x4 the two notches might suggest.

View full M.2 spec sheet →

PCIe Add-in Card (AIC) SSDs, commonly called HHHL (Half-Height, Half-Length), plug directly into a PCIe expansion slot like a graphics card rather than using M.2 or U.2 connectors -- trading compactness for the far greater power delivery and cooling surface area a full expansion card provides.

View full PCIe AIC spec sheet →

Specification Comparison Table

8 Parameters
Parameter / Spec
Common Sizes
2230, 2242, 2260, 2280, 22110
B-Key
SATA or PCIe x2
M-Key
SATA or full PCIe x4 (NVMe)
B+M-Key (dual notch)
SATA or PCIe x2 only -- not x4
Introduced
November 2013 (as "NGFF")
Physical Form Factor
Half-Height, Half-Length (HHHL) PCIe expansion card
Slot Power Available
Up to 75W (PCIe x16 slot)
Typical Use
High-performance enterprise/datacenter and enthusiast drives