Vista - SD card as ReadyBoost causes 1 min shutdown. Why?

Tried Micro SD HC 4GB in a Kingston mini USB.
HDTach, etc measures it at 18MB/s, 1.0ms access, 17.1MB/s average.

With it plugged in, shutdown takes about 60 seconds.
Remove it and shutdown takes perhaps 5 seconds.

Is there a card that won't do this?

(I see nothing in Events)

(Vista is on Raptor, rest of system is on 2 Hitachi . All are SATA.

tia!!!!!!!
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Kris
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Gigabyte GA-EP45-UD3P | E7200 2.53@xxxxxx
| 2x1gb OCZ Reaper1150@xxxxxx | EVGA 9800GTX+ N873 |
LiteOn DH401S08C at CP56 BluRay player | Hannspree HF289H 28" |
Raidmax RX530-SS psu | Vista Ult 32 SP1

On Fri, 2 Jan 2009 23:30:33 -0500, Kris wrote:
seems to be fixed - that microSD thing was a Kingston reader packaged with
a 2gb card
like this: http://www.newegg.com/Product/Produc...82E16820134545
I tried the original 2GB card in it and did NOT get the 1 minute shutdown
artifact - more like 9 secs or so. Might be that the 4GB was HC, or might
be that the reader simply wasn't good for 4GB, though it read it okay.
This setup tests at 20GB/s and 0.8s access.
--
Kris
----------
Gigabyte GA-EP45-UD3P | E7200 2.53@xxxxxx
| 2x1gb OCZ Reaper1150@xxxxxx | EVGA 9800GTX+ N873 |
LiteOn DH401S08C at CP56 BluRay player | Hannspree HF289H 28" |
Raidmax RX530-SS psu | Vista Ult 32 SP1