First post, by vanderlinde
It seems that ChatGPT is able to craft, design me a fully working slotket for Slot A that you could use, more future CPU's (Socket A) into your K7 / Slot A Motherboard.
But, since the project requires lots of work, i'm stepping away from it. It's likely the other way around as well, where you can insert K6 based CPU's into a K7 based Board.
Note: a slotket for a Slot A has never been made. After Slot A it was S462 or Socket A. AI Summerize:
Concept Project: Active Slot A → Socket A Adapter / “AMD Slotket”I’m exploring the design of an AMD Slot A to Socket A / Socket 462 adapter, basically an AMD version of an Intel slocket, but much more complex.The goal would be to allow selected Socket A Athlon/Duron CPUs to run on older Slot A motherboards, such as AMD 751/Irongate or VIA KX133-based boards. This would not be a simple passive pin adapter. It would likely need to be an active interposer board with startup-configuration logic, voltage handling, multiplier/VID controls, and possibly BIOS support.Basic ideaThe adapter would plug into the original Slot A edge connector on the motherboard and provide a Socket A / Socket 462 ZIF socket on top.The concept board would include:Slot A gold-finger edge connectorSocket A / Socket 462 ZIF socketCPLD/FPGA for startup/ROMSIP patchingVID/FID jumper blocks for voltage and multiplier controlVoltage-regulation and filtering componentsDebug/test headersMechanical support bracket for the Socket A coolerOptional adapter ID or configuration EEPROM/registersI made some concept drawings showing:The adapter by itselfThe adapter installed on a Slot A motherboardThe adapter installed with a Socket A heatsink/fan coolerThese are only concept renders for discussion, not final CAD.Why this is difficultSlot A and Socket A are both AMD K7-family platforms, but they are not directly interchangeable.The biggest issue is not just pin mapping. The hard part appears to be the bus startup configuration, especially the difference between older Slot A-style signaling and later Socket A behavior. Some Socket A CPUs may need push-pull bus driver configuration, while older Slot A boards expect different startup behavior.Because of that, a passive adapter would probably not work reliably. The design would likely need a small CPLD or FPGA to intercept or patch the CPU startup/ROMSIP configuration before the CPU begins normal bus communication.First realistic targetThe first realistic test target would be conservative:Slot A board: AMD 751/Irongate or VIA KX133 boardCPU: early Socket A Thunderbird or DuronFSB: 100 MHz / 200 MT/s effectiveGoal: POST, enter BIOS, boot DOS/Linux, then stress-testLater CPUs such as Palomino, Thoroughbred, or Barton might be possible later, but they add more problems: BIOS support, multiplier mapping, power draw, and FSB compatibility.BIOS / firmware ideaThe first step should probably be patched stock BIOS, not a full open-source BIOS.The original BIOS already knows how to initialize the motherboard chipset, SDRAM, Super I/O, PCI routing, AGP, and onboard devices. Replacing all of that from day one would make the project much harder.Suggested firmware path:Build Rev-A hardware prototypeUse a patched stock Award/AMI BIOS to accept the new CPUAdd or modify CPU ID / microcode-style handling where possibleAdjust ROMSIP/startup tables if needed
Once hardware is proven, investigate a coreboot + SeaBIOS portA future open-source firmware path could be:coreboot + SeaBIOS + slotket-specific hardware detection + CPLD startup patchingHowever, coreboot cannot fix the problem if the CPU never reaches executable code, so the adapter hardware still needs to handle the early startup configuration.Rough cost estimateThis would not be a cheap adapter at prototype stage.Estimated hobby prototype cost:First bare prototype PCBs: around $150–$700Parts per adapter: around $100–$400Assembly/rework/tools/test hardware: $300–$1,500+First serious prototype effort: roughly $800–$2,500 if tools are already availableMore realistic full bench/debug budget: $2,000–$5,000+If the design were proven and produced in a small batch, finished units might still cost around $250–$500 each, depending on sockets, CPLD programming, brackets, testing, and documentation.Main risksIncorrect Vcore/VID could kill CPUs or motherboardsWrong bus mode could cause electrical contentionEV6 signal routing may be sensitive to trace length and impedanceSlot A boards may not provide enough current for later Socket A CPUsBIOS may fail before useful debugging is possibleSocket A cooler load needs mechanical support to avoid damaging the slot or CPU dieCurrent project statusAt this stage this is a concept/proposal, not a working product.The next useful steps would be:Choose one target motherboard familyBuild a full Slot A ↔ Socket A pin and signal mapIdentify all required power, clock, reset, VID, FID, and ROMSIP linesDesign a minimal Rev-A test adapterAdd CPLD/FPGA logic for startup configuration experimentsPatch stock BIOS for basic CPU recognitionTest with cheap/sacrificial Slot A boards and early Socket A CPUsHelp wanted / discussion pointsI’m especially interested in input from people with experience in:AMD Slot A electrical designSocket A / Socket 462 pinout and signal behaviorAMD 751/Irongate and VIA KX133 chipsetsROMSIP / SIP tablesAward/AMI BIOS modificationcoreboot on old K7-class hardwareHigh-speed PCB layout for EV6 bus signalsCPLD/FPGA interposer logicVintage AMD motherboard repair/testingThe goal is to find out whether a practical AMD Slot A → Socket A active slotket can be built, and what the cleanest path would be for hardware and BIOS support.