Dell XPS 720 (Mid 2007) - Manual (Page 177)

Appendix
177
5 Recenter the rollers in their channels if they are misaligned. Ensure that fluff from the swab is not left
on the rollers.
6 Replace the ball and retainer ring, and turn the retainer ring clockwise until it clicks into place.
Floppy Drive
NOTICE:
Do not attempt to clean drive heads with a swab. The heads may become misaligned and prevent the
drive from operating.
Clean your floppy drive using a commercially available cleaning kit. These kits contain pretreated floppy
disks to remove contaminants that accumulate during normal operation.
CDs and DVDs
NOTICE:
Always use compressed air to clean the lens in the optical drive, and follow the instructions that come
with the compressed air. Never touch the lens in the drive.
If you notice problems, such as skipping, with the playback quality of your discs, try cleaning the discs.
1 Hold the disc by its outer edge. You can also touch the inside edge of the center hole.
NOTICE:
To prevent damaging the surface, do not wipe in a circular motion around the disc.
2 With a soft, lint-free cloth, gently wipe the bottom of the disc (the unlabeled side) in a straight line
from the center to the outer edge of the disc.
For stubborn dirt, try using water or a diluted solution of water and mild soap. You can also purchase
commercial products that clean discs and provide some protection from dust, fingerprints, and
scratches. Cleaning products for CDs are safe to use on DVDs.
FCC Notices (U.S. Only)
Most Dell computer systems are classified by the Federal Communications Commission (FCC) as
Class B digital devices. To determine which classification applies to your computer system, examine all
FCC registration labels located on the bottom, side, or back panel of your computer, on card-mounting
brackets, and on the cards themselves. If any one of the labels carries a Class A rating, your entire system
is considered to be a Class A digital device. If all labels carry an FCC Class B rating as distinguished by
either an FCC ID number or the FCC logo, (
), your system is considered to be a Class B digital
device.
Once you have determined your system’s FCC classification, read the appropriate FCC notice. Note that
FCC regulations provide that changes or modifications not expressly approved by Dell could void your
authority to operate this equipment.
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two
conditions:
1 This device may not cause harmful interference.
2 This device must accept any interference received, including interference that may cause undesired
operation.