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386 Processors - Questions and Answers

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Question:
What is an IBM 386SLC, and how does it differ from other 386 chips?
Answer:
It is an IBM-developed derivative of the Intel 386SX chip, called the 386SLC.

Question:
How fast is the 386SLC?
Answer:
This processor, while running at the same 20MHz speed as the 386SX, performs as much as 88% faster than the equivalent speed 386SX chip, due to an internal 8K processor cache. This is similar in concept to the internal cache in the Intel 486 processor.

Question:
At what clock speeds does the 386SLC operate?
Answer:
The processor speeds offered are 16 and 20MHz.

Question:
What does the "SLC" in 386SLC processor stand for?
Answer:
It stands for "SX processor, Low-power, Cached."

Question:
Does the IBM 386SLC processor include integrated power management capabilities, like the Intel 386SL processor?
Answer:
Yes. The power management capabilities are not identical at the hardware level, but they are compatible at the software interface level.

Question:
Is this chip Intel 386/386SX-compatible?
Answer:
Yes; every bit as software compatible as the 386SX itself. It has been certified as such by Intel, and in fact was developed with Intel's cooperation. It is even pin-compatible; however the 386SX as defined by Intel leaves some pins unused. The IBM 386SLC uses some of these pins for power management, asynchronous operation, and cache controllability. This is why a 386SX can't simply be removed and replaced by the 386SLC. Additional circuitry is needed by the system to utilize these advanced features. Thus the reason for the PS/2 Cached Processor Option.

Question:
Does the IBM 386SLC processor use a "static" design, suitable for low-power application?
Answer:
Yes.

Question:
How does an IBM 386SLC compare to the Intel 20MHz 386SX, performance-wise?
Answer:
The 386SLC processor uses an internal 8K cache. The standard Intel 386SX processor has no internal cache. Compared to a standard Model 56/57 SX the difference is up to 88% faster. Some PCs add an external cache for better performance. By comparison, the internal cache makes the Models 56/57 with the 386SLC installed as much as 67% faster than competitive cached 20MHz 386SX systems, and even as much as 7% faster than 25MHz 386DX systems!

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	Hint Category	Performance
	Date Created	20-07-98
	Last Updated	25-03-99
	Revision Date	25-03-2000
	Brand	IBM Options
	Product Family	Processor Upgrades
	Machine Type	386
	Model	All
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