Sony PCG-SRX99 VAIO User Guide (primary manual) User Manual page 57

Notes on using i.LINK optical disc drives

You can use the supplied Application Recovery and System Recovery CDs with an i.LINK optical disc drive. See
Application and System Recovery CDs

Do not use an optional i.LINK optical disc drive and an optional optical disc drive with PC Card at the same time.
Connecting both drives may cause a system malfunction.
for more information.
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