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I don't have one to test this at the moment but I plan to buy an 8GB card and use it with ReadyBoost (Windows 7) on my laptop.

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up vote 5 down vote accepted

No problem with exFAT but whether you can use it for Readyboost really depends on the read/write speed of the card.

The device must be capable of 2.5 MB/s read speeds for 4 KB random reads spread uniformly across the entire device, and 1.75 MB/s write speeds for 512 KB random writes spread uniformly across the device.

Windows 7 automatically tests this for you when you plug it in.

There are workarounds but it kind of defeats the point as the performance would not be good enough to benefit from the extra cache.

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Yes to the content of your question, you can format, partition and/or do pretty much anything to most flash memory (sticks/cards).

I am not 100% sure about your title line - exfat, I do not see a problem, but cannot say for sure. If using Readyboost, I would just stick with default FAT.

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FAT won't use over 4GB on my 8GB Flash Drive so I had to format it as exFAT in Windows 7 after which I was able to allocate 8GB for ReadyBoost. Thanks! – ymasood Sep 7 '09 at 21:29

Yes, I just formatted a 4GB SD card with exFAT.

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