A Single Edge Contact Cartridge (SECC) is a central processing unit (CPU) component designed to hold certain Intel microprocessors such as Pentium II and Pentium III, Pentium Pro and Celeron. The SECC is also known as Slot 1 because it is inserted into Slot 1 on the motherboard.
Slot 1 is in reference to the electrical and physical specifications of the connector for both single- and dual-processor configurations of the various Intel microprocessors. It was designed to remove L2 cache memory off the motherboard onto the CPU for better efficiency and scalability. The card was easily inserted into Slot 1 and eliminated the chance of pins being broken or bent as with older socket versions.
Slot 1 was the replacement for Socket 8. Slot 1 has L2 cache embedded into the die of the CPU. It uses a Coppermine core with Advanced Transfer Cache (ATC) for better pipelining. Socket 8 did have L2 cache embedded on the CPU, but it was located on a circuit board outside the core.
The SECC was superseded by the SECC2 in some Pentium II 450s and all Pentium IIIs. The SECC2 supports direct contact with the heatsink allowing a more proficient cooling architecture.
For backward compatibility, a converter card called slotket could be used to contain Socket 8. The slotkets for Socket 8 were rarely used but allowed a Pentium Pro CPU to be utilized in a Slot 1 motherboard. Additionally, there were slotkets for the Socket 370 CPU that could be inserted into Slot 1 which was commonly used. Most of the newer slotkets for the Socket 370 CPU were fitted with a voltage regulator so that the motherboard allowed the device.
Depending on the CPU, various clock rates could be attained:
- Pentium II: 233–450 MHz
- Celeron: 266–433 MHz
- Pentium III: 450–1,133 MHz
- Celeron and Pentium III using slotkets: Up to 1,400 MHz
- VIA Cyrix III using Slotkets: 350–733 MHz
- VIA C4 using Slotkets: 733–1,200 MHz