computer science

HyperZ

HyperZ is a computer science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand HyperZ rather than just read about it. In short: HyperZ is the brand name for a set of processing techniques developed by ATI Technologies—which later merged with Advanced Micro Devices (AMD)—and implemented in its Radeon-GPUs. HyperZ was announced in November 2000 and was still available in the TeraScale-based Radeon HD 2000 Series and in Graphics Core Next-based graphics products.

Key takeaways

HyperZ belongs to computer science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect HyperZ to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of HyperZ from memory before moving on to harder problems.

Reference excerpt

HyperZ is the brand name for a set of processing techniques developed by ATI Technologies—which later merged with Advanced Micro Devices (AMD)—and implemented in its Radeon-GPUs. HyperZ was announced in November 2000 and was still available in the TeraScale-based Radeon HD 2000 Series and in Graphics Core Next-based graphics products. On the Radeon R100-based cores, Radeon DDR through 7500, where HyperZ debuted, ATI claimed a 20% improvement in overall rendering efficiency. It stated that with HyperZ, Radeon could be said to offer 1.5 gigatexels per second fillrate performance instead of the card's apparent theoretical rate of 1.2 gigatexels. In testing it was shown that HyperZ did indeed offer a tangible performance improvement that allowed the less endowed Radeon to keep up with the less efficient GeForce 2 GTS.

Functionality HyperZ consists of three mechanisms:

Z compression The Z-buffer is stored in a lossless compressed format to minimize the z-buffer bandwidth as Z read or writes are taking place. The compression scheme ATI used on Radeon 8500 operated 20% more effectively than on the original Radeon and Radeon 7500. Fast Z clear Rather than writing zeros throughout the entire Z-buffer, and thus using the bandwidth of another Z-Buffer write, a Fast Z Clear technique is used that can tag entire blocks of the Z-Buffer as cleared, such that only each of these blocks need be tagged as cleared. On Radeon 8500, ATI claimed that this process could clear the Z-Buffer up to approximately 64 times faster than that of a card without fast Z clear. Hierarchical Z-buffer This feature allows for the pixel being rendered to be checked against the z-buffer before the pixel actually arrives in the rendering pipelines. This allows useless pixels to be thrown out early (early Z reject), before the Radeon has to render them.

Versions of HyperZ With each new microarchitecture, ATI has revised and improved the technology.

HyperZ – R100 HyperZ II – R200 (8500-9250) HyperZ III – R300 in Radeon 9700 HyperZ III+ – R350 used in Radeon 9800, Radeon 9800 XL, Radeon 9800 Pro and Radeon 9800 SE HyperZ HD – R420 used in Radeon X700 to Radeon X850 XT PE

See also Irregular Z-buffer Depth map Rasterization

References

External links AMD press release about HyperZ

Illustrations

Worked examples

Example 1 — a first encounter with HyperZ

Start with the simplest possible case. Write down what HyperZ claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In computer science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to HyperZ before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about HyperZ ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of HyperZ

In research: HyperZ appears in computer science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses HyperZ in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: HyperZ is common in secondary-school and first-year university syllabi. It links to neighbouring topics AMD technologies, ATI Technologies, Computer hardware stubs, so understanding it makes those chapters shorter.
In everyday life: Look for HyperZ outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study HyperZ in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what HyperZ means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain HyperZ out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is HyperZ in simple terms?

Why does HyperZ matter?

Because it connects several computer science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study HyperZ?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on HyperZ.