Storage media

Cassette tape

As mentioned above, IBM equipped the model 5150 with a cassette port for connecting a cassette drive, and originally intended compact cassettes to become the 5150's most common storage medium. However, adoption of the floppy- and monitor-less configuration was low; few (if any) IBM PCs left the factory without a floppy disk drive installed. Also, DOS was not available on cassette tape, only on floppy disks (hence "Disk Operating System"). 5150s with just external cassette recorders for storage could only use the built-in ROM BASIC as their operating system. As DOS saw increasing adoption, the incompatibility of DOS programs with PCs that used only cassettes for storage made this configuration even less attractive.

"IBM PC" redirects here. For IBM-like PCs in general ("clones"), see IBM PC compatible.Don Estridge the Development Director

The IBM Personal Computer, commonly known as the IBM PC, is the original version and progenitor of the IBM PC compatible hardware platform. It is IBM model number 5150, and was introduced on August 12, 1981. It was created by a team of engineers and designers under the direction of Don Estridge of the IBM Entry Systems Division in Boca Raton, Florida.

Alongside "microcomputer" and "home computer", the term "personal computer" was already in use before 1981. It was used as early as 1972 to characterize Xerox PARC's Alto. However, because of the success of the IBM Personal Computer, the term came to mean more specifically a microcomputer compatible with IBM's PC products.

Asus Eee PC

The Asus Eee PC ("Eee" is pronounced [iː] as in "see"}) is a subnotebook/netbook computer by Asus and a part of Asus Eee product family. At the time of its introduction in late 2007, it was noted for its combination of a light weight, Linux operating system, solid-state drive and relatively low cost. Newer models have added the option of Windows XP operating system and traditional hard disk drives. Newer models have also increased in price, though they remain relatively inexpensive as laptops, and notably inexpensive for ultra-small laptops.

According to Asus, the name Eee derives from "the three Es," an abbreviation of its advertising slogan for the device: "Easy to learn, Easy to work, Easy to play".^[1]

Random-access memory

Random-access memory (usually known by its acronym, RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order (i.e., at random). The word random thus refers to the fact that any piece of data can be returned in a constant time, regardless of its physical location and whether or not it is related to the previous piece of data.^[1]

By contrast, storage devices such as tapes, magnetic discs and optical discs rely on the physical movement of the recording medium or a reading head. In these devices, the movement takes longer than data transfer, and the retrieval time varies based on the physical location of the next item.

The word RAM is often associated with volatile types of memory (such as DRAM memory modules), where the information is lost after the power is switched off. Many other types of memory are RAM, too, including most types of ROM and flash memory called NOR-Flash.

Pentium 4

The Pentium 4 brand refers to Intel's line of single-core mainstream desktop and laptop central processing units (CPUs) introduced on November 20, 2000^[1] (August 8, 2008 was the date of last shipments of Pentium 4s^[2]). They had the 7th-generation microarchitecture, called NetBurst, which was the company's first all-new design since 1995, when the Intel P6 microarchitecture of the Pentium Pro CPUs had been introduced. NetBurst differed from the preceding Intel P6 - of Pentium III, II, etc. - by featuring a very deep instruction pipeline to achieve very high clock speeds^[3] (up to 4 GHz) limited only by maximum power consumption (TDP) reaching up to 115 W in 3.6–3.8 GHz Prescotts and Prescotts 2M^[4] (a high TDP requires additional cooling that can be noisy or expensive). In 2004, the initial 32-bit x86 instruction set of the Pentium 4 microprocessors was extended by the 64-bit x86-64 set.

The original Pentium 4, codenamed "Willamette", ran at 1.4 and 1.5 GHz and was released in November 2000 on the Socket 423 platform. Notable with the introduction of the Pentium 4 was the 400 MT/s FSB. It was actually based on a 100 MHz clock wave, but the bus was quad-pumped, meaning that the maximum transfer rate was four times that of a normal bus, so it was considered to run at 400 MT/s. The AMD Athlon was running at 266 MT/s (using a double-pumped bus) at that time.

Pentium 4 CPUs introduced the SSE2 and SSE3 instruction sets to accelerate calculations, transactions, media processing, 3D graphics, and games. They also integrated Hyper-threading (HT), a feature to make one physical CPU work as two logical and virtual CPUs. The Intel's flagship Pentium 4 also came in a low-end version branded Celeron (often referred to as Celeron 4), and a high-end derivative, Xeon, intended for multiprocessor servers and workstations. In 2005, the Pentium 4 was complemented by the Pentium D and Pentium Extreme Edition dual-core CPUs.