AMD-751AC Advanced Micro Devices, AMD-751AC Datasheet
AMD-751AC
Specifications of AMD-751AC
Related parts for AMD-751AC
AMD-751AC Summary of contents
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... Preliminary Information AMD-751 System Controller Revision Guide Publication # 22564 Rev: B-1 Issue Date: February 2000 TM ...
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... AMD reserves the right to discontinue or make changes to its products at any time without notice. Trademarks AMD, the AMD logo, and combinations thereof, AMD Athlon, AMD-751, and AMD-756 are trademarks of Ad- vanced Micro Devices, Inc. Other product names used in this publication are for identification purposes only and may be trademarks of their respective companies ...
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... Occasionally AMD identifies deviations from or changes to the specification of the AMD-751 system controller. These changes are documented in the AMD-751 System Controller Revision Guide as errata. Descriptions are written to assist system and software designers in using the AMD-751 and corrections to AMD’s documentation on the AMD-751 system controller are included. This release documents currently characterized product errata ...
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... AMD-751™ System Controller Revision Guide 1 Product Marking Identification 1.1 Production Marking Family/Core AMD-751 Product Revision Table 1. OPN AMD-751AC 492-pin PBGA ATX Note: 2 Preliminary Information AMD-751 TM AMD-751AC B Date Code AMD 1999 c Valid Combinations for Ordering Parts Package Type Operating Voltage 3.135 V–3.6 V Valid combinations are configurations that are or will be supported in volume for this device ...
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... Product Errata This section documents AMD-751 system controller product errata. A unique tracking number for each erratum has been assigned within this document for user convenience in tracking the errata within specific revision levels. Table 2 cross-references the revisions of the processor to each erratum. An “X” ...
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... Arbitration Latency Due to No Bus Preemption Products Affected. C3 Description. The AMD-751 PCI arbiter can impose long latencies on external PCI bus masters when any master that currently owns the bus is attempting long transfers due to not correctly supporting bus preemption. When a PCI master’s bus grant is active and another master requests the bus, the arbiter should immediately deassert the grant to the first master, thus preempting the first master ...
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... Description. If DMA is active when ARB_DIS is set, the system can hang. Potential Effect on System. System hang could occur. Suggested Workaround. Prior to setting ARB_DIS, software suspends all DMA activity. Resolution Status. Fixed in a future revision of the AMD-751 system controller. 8 GART Requestors Do Not Work With TLB Caches Off Products Affected ...
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... Products Affected. C3, C5 Description. An incomplete AMD Athlon™ system bus disconnect sequence (from the AMD Athlon processor) can hang the AMD-751 system controller. The AMD Athlon may not complete a disconnect sequence when using STPCLK-throttling power management. Potential Effect on System. This problem can occur with ACPI thermal zone support (thermal-throttling power management) or processor C2/C3 support enabled ...
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... Description. Voltage on the Vcc (3.3-V supply) pins cannot exceed the voltage on the 5-V reference pin (Ref_5V). Potential Effect on System. The AMD-751 can go into a latch-up state, and permanent damage to the part may result. Suggested Workaround. Specify the system power supply whose outputs ramp up and ramp down, such that the 3.3V outputs never supply voltage higher than the 5-V outputs. For more information, see the AMD Athlon™ ...
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... S3 Savage4 graphics card. This behavior to the system controller is caused by the software/driver when write combining is enabled and is not considered appropriate nor indicative of any common software technique. Write combining is enabled when the AMD AGP miniport driver is installed. Potential Effect on System. System hangs. ...
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... AGP AD_STB[1:0] Strobe Glitch with Nvidia NV10-Based (GeForce) Cards Products Affected. All revisions (C3 and C5) Description. The AMD-751 system controller’s AD_STB[1:0] signals may experience noise due to strong drive strengths. This noise may result in signal glitches, causing incorrect information to be strobed into the AGP adapter. ...
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... Vendors developing new AMD-751 based motherboards should implement pulldown resistors on the MAA[14:0] and MAB[14:0] address buses. Use of this termination method will improve the timing margins. Please consult your OEM or AMD specialist for specific values. Resolution Status. All future motherboards should be implemented with the suggested termination method ...
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... Reset — — Bits 7–0 AMD-751™ System Controller Revision Code (RO) - The most-significant nibble indicates the die revision and the least-significant nibble represents the stepping. (For example, 00h = Revision A0; 01h = Revision A1; 10h = Revision B0; 21h = Revision C1; 25h = Revision C5; etc.) Preliminary Information AMD-751™ System Controller Revision Guide ...
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... AMD Athlon™ Processor BIOS, Software, and Debug Tools Developers Guide (order# 21656) AMD Athlon™ Processor Data Sheet (order# 21016) For the latest updates, refer to www.amd.com and download the appropriate files. For documents under NDA, please contact your local sales representative for updates. ...