immediately resume from standby

Hello,

Since some time now, I have a problem with my standby function in Windows
XP. Sometimes when I push the sleep button on my keyboard, the pc goes into
standby (S3) but immediately resumes. After a few seconds I push again and
it goes and remains in standby.

It looks it happens when the pc has been on for some time. Especially when
the monitor has been powered off by the power save options. I already looked
at the repeat function of the keyboard, but this is set low.

I cannot reproduce this error, so I hope someone can help me. I've tried
almost everywhere, because I don't know who a has the answer...

Thanks in advance,
Mike

Windows XP Pro SP1 Dutch
AMD Athlon XP 2000+
GigaByte 7VRXP (2.0?), ACPI enabled etc.
Logitech Cordless Desktop Optical (latest iTouch)
Standby = S3 (Suspend to RAM)

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