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  1. Lazzer408

    RMA a promotional card?

    He built a new PC around this card. He said it worked until he enabled XMP. Saved and exited then got up to use the restroom. When he got back the screen was dead. Never worked again. He even went as far as returning his CPU, mobo, and memory. Still nothing. Hasn't played a single game. I don't...
  2. Lazzer408

    RMA a promotional card?

    There's a model sticker on it. The serial number sticker from what I can tell is normally located just above the PCIe edge but is missing. No indication it was ever there.
  3. Lazzer408

    RMA a promotional card?

    Robeytech was the person who did the promotion on Twitch. My friend asked him to help but Robeytech just blocked him and washed his has of the situation. Robeytech was also the one that said it came from AMD so deal with them for RMA. The card has no serial number. That's the other issue with...
  4. Lazzer408

    RMA a promotional card?

    Yes dual bios. Neither works.
  5. Lazzer408

    RMA a promotional card?

    I've read a lot of people are having issues with the RX5700 cards. This one is a no post situation. BIOS hangs at code b2, initializing the GPU's firmware, and hangs there. If I boot off the onboard, the 5700 does show up in device manager. Plugging in a monitor afterwards does nothing. No...
  6. Lazzer408

    RMA a promotional card?

    A friend won a Powercolor RX5700 and it's DOA. Powercolor says contact AMD because they provided it as a promotional item. AMD says contact Powercolor because it's their card. Any advice where to go from here?
  7. Lazzer408

    So you want PWM control of your 3-pin fan?

    It's going to be something along these lines. Not sure how it will work with the PWM signal being 5v but a low/hi signal driving this circuit will give you a low/hi out. Choose a Q1 large enough to drive your load, Choose R2 to drive enough current into Q1's base. Q2 should be large enough to...
  8. Lazzer408

    So you want PWM control of your 3-pin fan?

    High side switching via. MOSFET will require gate drive >12v. Use a BJT transistor. Because it's switched mode, losses are minimal. Typically (.6V*A)*PWM=dissipation. If you had 3 amps worth of fans (a lot), and PWM is 100%, you will only have ~1.8w of heat to dissipate from the transistor. I'm...
  9. Lazzer408

    So you want PWM control of your 3-pin fan?

    All of that had been mentioned in the thread.
  10. Lazzer408

    So you want PWM control of your 3-pin fan?

    The capacitor should be placed in parallel with your supply voltage. Duty cycle (pulse width) is controlled by the motherboard. If you can't adjust it in the BIOS then there's nothing you can do about it.
  11. Lazzer408

    So you want PWM control of your 3-pin fan?

    The PWM frequency is a function of the motherboard. All the board does is ground the PWM pin at varying widths. If you don't have complete control over the fan curves in your BIOS, this circuit may not work for you. The "correct" way to control a fan (using Intel's PWM spec) is a more...
  12. Lazzer408

    So you want PWM control of your 3-pin fan?

    Put your meter on AC and measure that charger. Read anything? If so, that's the ripple in the DC caused by the chargers lack of filtering (they don't need it). Next, place a capacitor in parallel with the charger and measure the DC voltage. Is it higher? If so, that's the peak DC voltage coming...
  13. Lazzer408

    So you want PWM control of your 3-pin fan?

    I think it's in quotes because we have no idea of knowing what type of charger it is. If it's a trickle charger for lead acid batteries, then it's likely much higher then 12v and it's not DC either. If the fans run full speed with the PWM unplugged, your gate drive is ok. What happens with you...
  14. Lazzer408

    So you want PWM control of your 3-pin fan?

    He mentioned in #79 that he tried the charger... "with a few Deltas and San Aces, 8 fans total, they all seemed to run full bore with no PWM connected". I think it's in his computer now.
  15. Lazzer408

    So you want PWM control of your 3-pin fan?

    Not a very good component but RDS(on) at 4v is .07 ohms so you 4.1v is plenty of gate voltage. NTE parts are junk (for future reference) but not the cause of your problem. The switching frequency is a function of the motherboard and should be around ~20khz. What do the fans do if you pull the...
  16. Lazzer408

    So you want PWM control of your 3-pin fan?

    Are you using a logic-level mosfet?
  17. Lazzer408

    So you want PWM control of your 3-pin fan?

    Which hurts who in what way? Information doesn't have a "sell-by" date. If people are still benefiting from the thread, it's not dead.
  18. Lazzer408

    So you want PWM control of your 3-pin fan?

    What's that have to do with anything?
  19. Lazzer408

    So you want PWM control of your 3-pin fan?

    Sounds like it's working fine. Good job.
  20. Lazzer408

    So you want PWM control of your 3-pin fan?

    Connect it to your 12v source. PWM lead should have ~5v on it. With PWM lead disconnected, the fan should run full speed. With the PWM lead grounded, the fan will stop. I'll look over your pics tonight. Velict's diagram looks fine other then the diode's anode connection doesn't have a dot...
  21. Lazzer408

    So you want PWM control of your 3-pin fan?

    Did you bench test it?
  22. Lazzer408

    So you want PWM control of your 3-pin fan?

    I'm going to add another circuit to this thread that may help you guys. This circuit CREATES a PWM signal that can be used to manually control 4-pin fans. The potentiometer is labeled "throttle" because this was part of a DC motor controller I'm designing. Frequency is controlled by C1. R7 may...
  23. Lazzer408

    So you want PWM control of your 3-pin fan?

    Looking at the schematic in post 7, you can probably eliminate R1 and Q2 and place the zener where Q2 was. When PWM calls for full speed, you should see ~11.45v on the fan due to the C-E voltage drop across Q1. When PWM calls for 0, the minimum speed is set by the 100k variable resistor...
  24. Lazzer408

    So you want PWM control of your 3-pin fan?

    None of the fans are modulated by that circuit itself. The circuit is just a switch being modulated by the motherboard's PWM pin. As for the PWM pin... PWM high (5v or not connected) = Fan at 100% PWM low (grounded by motherboard) = Fan at 0% PWM 50% = Fan at 50% (6v) The schematic you just...
  25. Lazzer408

    So you want PWM control of your 3-pin fan?

    Glad you figured it out. How is it handling the load of so many fans?
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