Is the SN850X worth the extra over the SN770?

Yes if you write large files often or want maximum game load speed. For booting Windows and playing games, the SN770 is close enough that most shoppers will not notice.

Which is better for a PS5?

The SN850X. It clears Sony's speed requirement with headroom, and its DRAM cache helps with large installs. The SN770 also works but is slower.

Both carry 5-year warranties. The SN850X has the higher endurance rating per terabyte, so it tolerates more total writes.

Will either fit my laptop?

Both are M.2 2280 NVMe drives, so they fit any slot that takes that size. Check that your slot is PCIe 4.0 to get full speed.

Do I need a heatsink?

The SN850X benefits from one under sustained load. The SN770 runs cooler and usually does not need one.

Which has the better rating?

The SN770, at 4.7 from 369 ratings versus 4.5 from 852 for the SN850X. Both are well rated.

WD Black SN850X NVMe SSD vs WD_BLACK SN770 1TB NVMe SSD

Buy the SN850X if you move large files, run a DRAM-cached workload, or want the fastest gaming drive; buy the SN770 if you want a solid Gen4 drive for less. The SN850X 1TB is $245.00 as of October 30, 2026, while the SN770 1TB is $99.99 at its low as of November 7, 2026, against a high of $199.99 on November 6. That gap is the whole decision: the SN850X is the faster drive, the SN770 is the value pick.

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