[weaksauce]

It fails the test, WTF?! I've got a kingston 1GB MMCPlus and a SanDisk MMC 1GB but only the sandisk can have readyboost. What's wrong with MMCPlus?

edit: ok got to use the sandisk one so it's ok but I still think it's strange the kingston card didn't work.

[Rainbow Man]

Maybe it is too slwo? I don't know what qualifications flash storage have to meet to be xompatible but have you noticed any speed differences?

Seems to me larger flash cards/USB sticks often are aslower than smaller ones.. Bit of a bummer that one.

Peace.

[Albuquerque]

Rainbow has it exactly right -- in order to be useful as a performance enhancer the flash media needs to meet a minimum read, write and random access speed criteria before it will be used.

Many of the larger devices are meant to have data stream-written to them (ie high speed, high megapixel camera.) Readyboost needs a device with high read and write speeds, along with high speeds under fully random accesses. Most "big" flash media don't meed that criteria in the way they're designed.

My ancient Kingston 256mb econo-class flash USB stick is readyboost compliant, but a year-old 80x 4GB SD card isn't. Guess where it fails? Random access.

If you want to know why your device is rejected, Vista logs that data in the performance event logs. Go looking for readyboost and you'll find where it does the performance profiling and reports the data (and if that data meets the requirements.)

[weaksauce]

"The device (USB2.0 CBO CardReader) will not be used for a ReadyBoost cache because it has insufficient read performance: 1248 KB/sec."

Turns out this card can't handle video recording on camera either. It's strange, I figurered an MMCPlus card would be faster than a regular of the same size. What the hell does the "plus" stand for? Plus extra slow performance?