# PC66

> speed rating of SDR SDRAM

**Wikidata**: [Q7118487](https://www.wikidata.org/wiki/Q7118487)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/PC66)  
**Source**: https://4ort.xyz/entity/pc66

## Summary
PC66 is the initial speed rating for SDR SDRAM, representing the 66 MHz memory bus standard. It defined the fundamental operating speed for the first generation of synchronous DRAM.

## Key Facts
-   PC66 is specifically defined as the speed rating of SDR SDRAM.
-   PC66 is a subclass of SDR SDRAM, the first generation of synchronous dynamic random-access memory.
-   PC66 has 2 sitelinks on the knowledge base.
-   The English Wikipedia entry title for PC66 is "PC66".
-   PC66 has entries in two languages: Arabic ("بي سي ٦٦") and English ("en") on Wikipedia.
-   The Wikidata description for PC66 states it is the "speed rating of SDR SDRAM".
-   PC66 has a Google Knowledge Graph ID: `/g/125n1dn92`.

## FAQs
### Q: What is PC66?
A: PC66 is the speed rating indicating a 66 Megahertz (MHz) memory bus speed standard for SDR SDRAM. It defines the core operating speed for the first synchronous DRAM generation.

### Q: How is PC66 different from other SDR SDRAM ratings?
A: PC66 is the foundational speed rating for SDR SDRAM, setting the baseline at 66 MHz. Higher ratings like PC100 or PC133 represent faster memory bus speeds, but PC66 defines the initial standard.

### Q: Why is PC66 important for SDR SDRAM?
A: PC66 specifies the original clock speed (66 MHz) at which SDR SDRAM was designed to operate, establishing the fundamental performance parameter for the first synchronous DRAM technology.

### Q: What does the "66" in PC66 stand for?
A: The "66" in PC66 directly refers to the 66 Megahertz (MHz) memory bus clock speed that defines this specific speed rating for SDR SDRAM.

## Why It Matters
PC66 matters because it established the first standardized speed benchmark for SDR SDRAM, the precursor to modern DDR memory. By defining the 66 MHz operating speed, PC66 provided a crucial reference point for the nascent synchronous DRAM market. This standardization was essential for system compatibility and performance expectations during the late 1990s, allowing manufacturers to produce components that worked reliably together. Although later superseded by faster standards like PC100 and PC133, PC66 laid the groundwork for understanding memory bus speeds and their direct impact on system performance. Its historical significance lies in being the foundational speed metric that defined the operating baseline for the entire SDR SDRAM generation.

## Notable For
*   Being the inaugural and foundational speed rating (66 MHz) for SDR SDRAM.
*   Defining the core memory bus standard for the first synchronous DRAM technology.
*   Establishing the initial performance benchmark against which faster SDR SDRAM speeds (like PC100/133) were measured.

## Body
### Definition and Scope
PC66 is specifically defined as the speed rating for SDR SDRAM. It represents the 66 Megahertz (MHz) memory bus speed standard for this first-generation synchronous dynamic random-access memory technology.

### Relationship to SDR SDRAM
PC66 is explicitly a subclass of SDR SDRAM. It is intrinsically linked to SDR SDRAM as its defining speed characteristic, specifying the operating clock speed of the memory bus for that standard.

### Knowledge Base Presence
*   **Sitelink Count:** PC66 has 2 sitelinks within this knowledge base.
*   **Wikipedia:**
    *   Title: "PC66"
    *   Languages: Arabic ("بي سي ٦٦"), English ("en")
*   **Wikidata:** Description states "speed rating of SDR SDRAM".
*   **Google Knowledge Graph:** Has an ID `/g/125n1dn92`.