Datasheet

Answers to Review Questions
85
11. A, C, G. DIMMs used in desktop-motherboard applications have one of three possible pin
counts. SDR SDRAM is implemented on 168-pin modules. DDR SDRAM and 16-bit RIMMs
are implemented on 184-pin modules. DDR2 and DDR3 are implemented on 240-pin modules
with different keying. Dual-channel RIMM modules have 232 pins. Modules with 200 and
204 pins are used in the SODIMM line, and there are no modules with 180 pins.
12. D. The USB 2.0 spec provides for a maximum speed of 480 megabits per second (Mbps
not megabytes per second, or MBps).
13. C, D. Bidirectional parallel ports can both transmit and receive data. EPP and ECP are
IEEE-1284 standards that were designed to transfer data at high speeds in both directions
so that devices could return status information to the system. The standard parallel port
only transmits data out of the computer. It cannot receive data. FireWire is specified by
IEEE 1394. IEEE 1284 does not specify serial protocols, such as RS-232 and USB.
14. C. The 1394 standard provides for greater data transfer speeds and the ability to send
memory addresses as well as data through a serial port.
15. B. USBs are used to connect multiple peripherals to one computer through a single port.
They support data transfer rates as high as 12Mbps, or 1.5MBps (for USB 1.1, which is the
option listed here).
16. D. IEEE 1284 standard defines the ECP parallel port to use a DMA channel and the buffer
to be able to transfer data at high speeds to printers.
17. D. The NLX form factor places expansion slots on a special riser card and is used in low-
profile PCs.
18. D. The unique thing about the Pentium II is that it was attached to a single edge contact
cartridge (SECC) for insertion into the motherboard, instead of the standard PGA package.
Athlon is an AMD processor, the early version of which was slot-based, but not considered
SECC, in any event.
19. D. Pentium 4 processors are always mated with memory mounted on DIMMs.
20. B. Although technically all slots listed could be used for video adapters, PCIe excels when
compared to the other options and offers technologies, such as SLI, which only make PCIe’s
advantage more noticeable.
86498book.indb 85 7/22/09 5:38:00 AM