HERETIC wrote:Don't know if we're talking about the same thing,but CrystalDisk has a entry on my C400-
BD-Factory bad block count-Raw value-52
He said he's running the Linux "badblocks" tool. Per the output, there are (at least) 32 unreadable sectors.
HERETIC wrote:I've always assumed NAND has spares to replace bad blocks at manufacturing level.
Yes, it does. But these are dealt with internally; if bad blocks are visible at the user level in a write-read-verify test (what badblocks does), the drive has a problem. A new drive should never have trouble coughing up data which was just written to it.
HERETIC wrote:What's the brand?
The described behavior would be incorrect regardless of brand.
HERETIC wrote:Is the capacity right?
It's certainly worth verifying the drive info and health as reported by SMART, to see if there are any anomalies. Since OP is apparently using Linux:
smartctl -a <device> (you may need to install an additional package from your repository first, e.g. in Debian/Ubuntu you need "smartmontools").
I would also run the same test with a known good drive connected to the same port and power connector, to rule out system level problems.