id like to clear a few things up in here
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My understanding is that any partition over 250GB will start to become corrupt. So, using F&G on a 400GB should be no problem.
partitions over 256gb become corrupt
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You can have partitions up to 2TB without corruption, but ONLY if you format with 64k clusters instead of 32k.
32k cluster partitions get corrupt at 512gb, 64k will corrupt at 1024gb (1tb) there is currently no app to format with 64k clusters (not needed since there are no HDs that big yet)
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What Xbox-application can format Xbox FATX-partitions with 64k clusters and is this by default supported on every BIOS?
xbpartitioner will automatically use
32k clusters on any partition it formats over 256gb
i believe your bios must be set to look at the HD partition table ("ignore HD partition table" box in xbtool is unchecked)
320gb and 400gb drives are fine using normal F+G partitioning (no special actions or apps needed) or using when xbpartioner to format large F