Hardware Information |
|
Expansion Cards Part 2: AGP
Expansion Cards Part 2: AGP The first in this series of Tech Tips on expansion cards took a look at the PCI slot, and the variety of devices that may find their home in one. Graphics cards are one of the many items that may be used in a PCI slot, but the demands of fast-paced video games require more speed and greater bandwidth than the PCI Bus can provide. Thus, the AGP slot was born, providing a dedicated interface to transfer graphics data only. The letters 'AGP' stand for Accelerated Graphics Port, and it is the term used to describe a dedicated, point-to-point interface that connects a video card directly to the system's memory and processor. AGP was first introduced by Intel in 1996, and is based off of their previous work in developing the PCI bus. Despite being based on PCI technology, the AGP and PCI slots on a motherboard are not interchangeable, so an AGP card can not be installed into a PCI slot, and vice versa. The initial release of AGP saw a sizeable performance boost over PCI, and the few revisions to the standard helped increase this even more as years went by. Other than having a dedicated path to the system's memory and processor, several other design features help AGP outperform PCI when it comes to graphics performance. Three of the other advancements: pipelining, side band addressing and graphics address remapping table are described below. Data transfer is improved through 'pipelining', a term used to describe the ability of an AGP graphics card to receive, and act upon, multiple instructions simultaneously. PCI data transfers require each piece of necessary information to be received separately before acting on any of it. Something called 'side band addressing' also provides AGP with a performance boost. Basically, additional lines of data are included with each packet to instruct the system as to where this data is to be used. PCI data transfers do not have this addressing information, and the system must look at the data itself in order to determine its destination. This is an obvious time saver, as well as a resource saver since the processor doesn't have to analyze all data just to determine the address. AGP allows the operating system to store texture maps in the system's memory which allows for more space, and perhaps faster access, rather than being limited to the use of graphics card memory only. Graphics art address remapping table, also known as GART, is a term used to describe a process that maps physical memory as virtual memory for the storage of texture maps. Basically, GART takes the system memory it is allowed to use to store texture maps and re-addresses it so that the system thinks these maps are now actually being stored in the frame buffer, or virtual memory. This might not sound like anything special, but this re-addressing requires that the texture map be written to memory only once and it is locked into place right where the AGP card can find it quickly. AGP can be broken down into different groups based on revisions to the specification (AGP 1.0, AGP 2.0, and AGP 3.0), as well as by the general speeds (1x, 2x, 4x, and 8x). There is overlap between the various categories, with AGP 1.0 supporting 1x and 2x, AGP 2.0 supporting 1x,, 2x, and 4x, and AGP 3.0 supporting 4x and 8x. For a complete break down of all the combinations available, please visit this page. Before taking a look at the specifications of AGP, let's have a refresher as to what was available on PCI prior to the birth of AGP. The standard PCI bus has a width of 32-bit, operates at 33 MHz, provides a maximum bandwidth of 132 MB/s (which has to be shared by all devices connected), and operates on 3.3V (or 5V on the original standard). The first version released was AGP 1.0 with a speed of 1x, which offered the following specifications: 32-bit bus width, operating at 66 MHz, providing a maximum bandwidth of 266 MB/s, and utilizing 3.3V. So, it can be seen that right out of the gate, AGP offered double the bandwidth of PCI. Each speed increase over 1x provided double the bandwidth as well as double the clock speed through the use of special signaling. So, AGP 2x offers a maximum bandwidth of 533 MB/s at a speed of 133 MHz, AGP 4x offers a maximum bandwidth of 1066 MB/s at a speed of 266 MHz, and AGP 8x offers 2.1 GB/s at a speed of 533 MHz. Given the timeline of the evolution of these cards, AGP 8x cards dominate today's marketplace. Finding some cards that are backwards compatible is possible, but the tricky part may be ensuring that the slot on the motherboard will accept them. Comparing the connector on this 128MB Apollo GeForce FX6600 GT card, to the connector on this 64MB Hercules 3D Prophet Ultra II card, and to the connector on this 256MB Chaintech GeForce FX5200 card shows that the first one is obviously different than the second two. The Apollo card is 8x only, the Hercules card is 4x/2x compatible, and the Chaintech card is 8x/4x, which results in different notches in the connector. AGP 1.0 only features a 3.3V connection, the release of AGP 2.0 saw the availability of both a 3.3V and 1.5V connector, and AGP 3.0 uses the same 1.5V, but only requires 0.8V for signaling. In order to protect cards of different voltages/formats, special keyed connectors were designed so that only the correct card could be installed on any motherboard. A universal connector was eventually released for AGP 1.0/2.0 which allowed cards of either voltage to be installed. For a schematic of the various connectors, please visit this page. Although AGP 3.0 can share in the use of a universal connection, many motherboards now only support 4x/8x cards based on the AGP 3.0 standard. Another specification for AGP was released between 2.0 and 3.0, and was referred to as AGP Pro. AGP Pro was intended to be the new standard to meet the demands of high powered graphics workstations, but it never really garnered widespread acceptance. Speeds of 1x, 2x, and 4x were supported with AGP Pro, and it utilized either a 3.3V, 5V, or a universal connector, similar to AGP 2.0. But, the AGP Pro connector was not the same size as the 'standard' AGP connector (see schematic at link above), meaning there were now three more possible connections to consider. An AGP Pro connection is longer than a standard AGP connection, and depending on the connector type, it could accept AGP 1.0 and 2.0 cards. Modern motherboards supporting AGP will specify what type of card is compatible with the board, so the guess work is eliminated when trying to match one with the other. For example, this Socket 754 Chaintech motherboard specifies that it has one AGP 4x/8x slot and this Biostar LGA 775 motherboard specifies that it has one 8x AGP slot. Final Words The AGP slot provided a much-needed boost to graphics cards as compared to the PCI slot, but game developers still managed to push the capabilities of this more powerful format to the edge. Something even faster was needed, and the next Tech Tip will take a look at that something in "PCI Express." PCI Express is not only destined to be the successor to AGP 8x, but due to its flexibility, perhaps to PCI as well. Computer tech tips and computer help
MORE RESOURCES: Asus vows to improve clarity surrounding warranty claims and astronomical hardware repair costs Tom's Hardware What we know so far about AMD's Zen 5 CPUs Windows Central Nvidia RTX 4070 Ti with memory mod easily beats RTX 4080 in Superposition benchmark - Tom's Hardware Bye Bye, AI: How to turn off Google's annoying AI overviews and just get search results Tom's Hardware Montclair hardware store to close after 131 years in business News 12 New Jersey My Mom and Dad Owned Competing Side-by-Side Hardware Stores. It Was a Lesson in Life. The Wall Street Journal OP police looking for 6 people involved in hardware store theft: WDAF FOX4 Kansas City Hardware Store In Montclair Closing After More Than A Century Montclair, NJ Patch Hardware Center in Paoli shutting down after nearly 73 years The Philadelphia Inquirer Ace Hardware Reports Increase in Q1 2024 Revenues Hardware Retailing Canyon ISD brings home hardware at UIL state tennis tournament Press Pass Sports Microsoft, Meta, Amazon, and other tech giants are cutting back on headcount—but their spending on hardware and ... Yahoo Finance Best Tech and PC Hardware Deals Tom's Hardware Overland Park police searching for suspects in multiple thefts KMBC Kansas City ACE HARDWARE REPORTS FIRST QUARTER 2024 RESULTS PR Newswire Intel-powered Aurora supercomputer fails to dethrone AMD-powered Frontier on Top500 list, again — claims spot as ... Tom's Hardware Three-year-old CPU beats Intel's fastest current chip in RAM benchmark — 7 GHz Core i9-11900K tops 8.3 GHz Core ... Tom's Hardware Enthusiast gets Windows XP running on an i486 — merging two dinosaurs from different eras Tom's Hardware Best Webcams for 2024 Tom's Hardware OpenAI's new assistant makes Apple's Siri look primitive, also announces GPT-4o and new desktop PC client (Updated) Tom's Hardware How Much Does It Cost To Open an Ace Hardware Franchise? 1851 Franchise Massive Dell blunder leaks Intel and Nvidia's mobile roadmaps — Nova Lake, Panther Lake CPUs and GENxx Nvidia ... Tom's Hardware Ace Hardware purchases 13 local chain store locations across central Illinois The State Journal-Register Melaco Sisters Hardware & Supplies Player of the Week: Zariell Pollard Lafourche Gazette DisplayPort 2.1 has a serious issue with UHBR-certified cables — it could explain Nvidia sticking with DP 1.4 on RTX ... Tom's Hardware Schoolmeester, Diani bring home hardware for Banks | Sports | forestgrovenewstimes.com Forest Grove News times CPU Benchmarks and Hierarchy 2024: CPU Rankings Tom's Hardware Western Digital rolls out new 2.5-inch HDDs for the first time in seven years: is 6TB the swan song for 2.5-inch hard ... Tom's Hardware US to increase tariffs on Chinese semiconductors by 100% in 2025 — officials say it protects the $53 billion spent on ... Tom's Hardware Homegrown European processor for supercomputers delayed by a year — chip upgraded to 80 cores, but timeline gets ... Tom's Hardware GPU Price Index 2024: Lowest price on every graphics card from Nvidia, AMD, and Intel today Tom's Hardware If you think PCIe 5.0 runs hot, wait till you see PCIe 6.0's new thermal throttling technique Tom's Hardware Hardware Wildlife Education Center Utah Division of Wildlife Resources Ace Hardware Brunswick | Ads | fredericknewspost.com Frederick News Post URI club sailing team heads to nationals, collects post-season hardware The University of Rhode Island Microsoft offers to relocate nearly 10% of China-based staffers to the US or allied nations — AI and cloud engineering ... Tom's Hardware Hardware visit Utah Division of Wildlife Resources Intel's 1500W TDP for Falcon Shores AI processor confirmed — next-gen AI chip consumes more power than Nvidia's ... Tom's Hardware Apple’s M4 iPad Pro offers stellar, high-performance hardware handicapped by iPadOS - MacDailyNews PS5 Best-Seller, Sales Drop For All Consoles - Europe Hardware Estimates for April 2024 - Sales VGChartz Nintendo Switch hacked to run Windows 11 on Arm, and it's just about as awful as you can imagine Tom's Hardware Intel's new Thunderbolt Share provides file and screen sharing without hurting network performance Tom's Hardware Ace Hardware partners with Webster Parish Council on Aging for fan drive Minden Press-Herald Area softball teams in search of hardware at various state tournaments Moscow-Pullman Daily News Daily Dish with K&K Hardware WHBF - OurQuadCities.com Windows translator makes PC games run on Android — Fallout 4 demoed at 30 fps using Winlator app Tom's Hardware Our newest hardware office in Taiwan The Keyword | Google Product and Technology News Curt's Ace Hardware Ribbon Cutting - Morristown, TN | Local News | citizentribune.com Citizentribune OLED monitor momentum expected to continue — analysts expect 1.34 million units shipped by year end Tom's Hardware Windows 11 24H2 will enable BitLocker encryption for everyone — happens on both clean installs and reinstalls Tom's Hardware 5 Best Hardware Wallets for DeFi in 2024 CoinCodex Asus quotes ridiculous $2750 fee to replace chipped GPU power connector— docs back up claims of egregious repair ... Tom's Hardware Save up to 50% on BBQs, lawn mowers and garden essentials during Home Hardware's massive pre-summer sale Yahoo Canada Shine On Newcomer Campbell Collects Major Hardware in CAA Softball Postseason Honors Colonial Athletic Association Stack Overflow bans users en masse for rebelling against OpenAI partnership — users banned for deleting answers to ... Tom's Hardware Full scan of 1 cubic millimeter of brain tissue took 1.4 petabytes of data, equivalent to 14000 4K movies — Google's AI ... Tom's Hardware |
RELATED ARTICLES
What is EEPROM ? EEPROM stands for Electrical Erasable Programmable Read Only Memory and also referred to as E²PROM. As the name suggest, an EEPROM can be both erased and programmed with electrical pulses. What is ESR Meter? All capacitors have a certain amount of resistance to the passage of AC current. ESR (Equivalent Series Resistance) is the sum of all internal resistances of a capacitor measured in Ohms. Testing Diode -The Accurate Way on How to Test Semiconductor Diode Using Multimeter Testing diodes is different from testing a resistor because you need a skill to do it. If you do not know or wrongly test a diode you will be unable to repair the equipment. Ten Ways (plus 1) to Save on Printer Ink and Toner Cartridges Are you getting tired of the high cost of printing? You're not alone. Many consumers are up in arms. ESR Meter - The Capabilities To Check Beyond Electrolytic Capacitor There is something good about esr meter because besides electrolytic capacitor it can be use to measure other type of capacitors such as the non polarity capacitor. From esr meter specification, it is usually mentioned only checking the electrolytic type. Generation Laptop In May 2005 U.S hardware history was made. Best DVDs for Your Personal DVD Player When bought personal DVD player, the very next thing to do is purchasing an important DVDs collection with your favourite movies, documentaries, shows, cartoons. Here are few hints before buying. Rear Projection TV Facts - Understanding the Pros & Cons of Rear Projection in the Home Theater Rear Projection Television - An Affordable OptionA great deal of consumer appeal for Rear Projection TV systems arise out of the shear simplicity that this product offers as an immediate solution to getting a bigger TV.No mess, no fuss, if you have the space, either visit your local big screen retailer - or better still, check at your favorite online electronics superstore - to order your product and get it delivered in just a few days; unpack the product and there you have a big screen TV in your living room ready for immediate use!Rear Projection TV Facts:As already stated, rear projection offers a most immediate solution to getting a bigger TV. Wireless Networking, Part 1: Capabilities and Hardware Wireless Networking, Part 1: Capabilities and HardwareThese days it isn't uncommon for a home to have multiple personal computers, and as such, it just makes sense for them to be able to share files, as well as to share one Internet connection. Wired networking is an option, but it is one that may require the installation and management of a great deal of wiring in order to get even a modestly sized home set up. How To Buy The Perfect Student Laptop If you are like most student's, money isn't exactly growing on trees. Choosing the right laptop can be a matter of saving yourself a lot of heartache and money at the same time. Dusting Your Computer - Keeping it Cool My mother always told me to dust, but I never did, mostly because I was lazy, but also because I couldn't find any tangible benefit to dusting. I just didn't see how I'd benefit from my room or my things being less dusty. Testing Capacitor-How To Test A Capacitor When Breakdown Under Load Have you ever come across power problem where onceyou switch on the power supply and the fuse blow? Youhave checked all the components in the power (primary)and secondary section and all the components seems to beok! Where is the fault? A fuse blown are usually causedby a shorted bridge rectifier, defective posistor, powertransistor or FET, shorted primary winding of switch modepower tranformer, shorted secondary diode and etc. Butin this article i'm gone to show you another secret of electronic troubleshooting tips. Got The Message that You Need New Ink Cartridges? We all know what it is like when that message flashes on the computer screen as you are printing off an important document. Your ink cartridge is low, replace soon! But, do you know what type of ink cartridges your printer needs? Do you know where to find ink cartridges to replace those? Is this going to be a long, difficult search that will cost you dearly? You don't have to dread that message at all. DVD Recorders: Getting Started IMO, these sd work 'like a VCR' as far as recording and playback. There are models w/ harddrives, VHS players, etc. How To Purchase A Quality Laptop Computers Case So you finally have that new laptop you have been drooling over for the past 3 months, only there is one problem -- You don't have a case for it. You've probably already laid down over a grand for the notebook and you're telling yourself that you don't want to spend another $70 for a case. Digital Camera Prints - Getting the Most for Your Money Digital cameras have really taken off in popularity in recent years. It's not uncommon anymore to see several people at an event with a digital camera. Printer Cartridges - Step Back in History You are working and trying to print out important documents when you discover that you are out of ink. This would have been a big drawback in the past. Intel Celeron vs Pentium The Celeron and Pentium Processors are two of Intel's best selling CPUs. They are found in a majority of home computer systems. Ergonomic Products 101 Human beings are scaling new heights day by day. Markets are becoming more and more complex and competitive. Lock Workstation Fast When you work in an office, it's important to lock your workstation every time you step away from your computer. A pain, but a security measure. |
home | site map |
© 2006 |