1. Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

mpc355 pump speed reading

Discussion in 'Overclocking & Cooling' started by Krony, Mar 17, 2011.

  1. Krony

    Krony New Member

    Joined:
    Jan 22, 2008
    Messages:
    288 (0.11/day)
    Thanks Received:
    59
    Location:
    England
    Hey, finally got my mpc355 wired up to my fan controler so i can slow it down a bit to save my ears :p
    All works fine and everything except the reading i get from the cpu header which is connected to the pump, using any program or even in the bios if i slow it down to about 2/3 speed i get all sorts of readings from 1500rpm to 38000rpm lol and if i take it a bit lower it shows 0rpm, i know it's running at a fast enough speed and i was under the impression that if the cpu header read that the fan was not spinning the pc would shut down for safety, it won't boot past the bios if it's running at about 1/2 speed (maybe 2000rpm) but if i speed it up to boot and then slow it down the pc still runs even tho the cpu header thinks the fan has stopped, just wondered if anyone else had similar issues.
     
  2. robal

    robal

    Joined:
    Aug 5, 2008
    Messages:
    485 (0.19/day)
    Thanks Received:
    111
    Location:
    Hampshire, UK
    Hi,

    The reason you're loosing RPM read below certain speed is that RPM signal is fed by the pump using the same voltage you supply it with.
    This varies from mobo to mobo, but basically when the voltage is too low, the monitoring chip is no longer able to distinguish 'ticks' and measure RPM.

    PWM-controlled fans/pumps don't have this problem, as power voltage is always 12V.

    Your BIOS should have settings to control dead fan protection. You may be able to switch it off (on the other hand, it's useful function).

    Cheers
     
    Krony says thanks.
  3. Krony

    Krony New Member

    Joined:
    Jan 22, 2008
    Messages:
    288 (0.11/day)
    Thanks Received:
    59
    Location:
    England
    Thx, yea i didn't want it off i just thought it shut the system down if it thought the cpu fan was not running not just would not boot, i guess i'll have to look at getting a flow sensor for peace of mind.
     
  4. slyfox2151

    slyfox2151

    Joined:
    Jan 14, 2009
    Messages:
    2,620 (1.12/day)
    Thanks Received:
    526
    Location:
    Brisbane, Australia
    Nope, the system will run as normal even with NO FAN connected.

    a default BIOS will tell you upon booting that there is no fan detected... Press F1 to continue.... however you can disable that warning.

    if the fan/pump is ever disconnected or stops working, your PC will in fact do nothing unless you set-up some sort of monitoring software.
     
    Krony says thanks.
  5. robal

    robal

    Joined:
    Aug 5, 2008
    Messages:
    485 (0.19/day)
    Thanks Received:
    111
    Location:
    Hampshire, UK
    That varies from mobo to mobo.
    Some mobos will not have this functionality or options.
    Some will have functionality, but not confugrable... and so on...

    The best solution is to have PWM controlled pump (like MCP35x).
    Voltage control is inherently unsafe... unless done by 'smart' controller that will detect stops.

    Other solutions: good FAN/pump controller that will take care of safety shutdown
    or: dedicated flowmeter connected to mobo's fan port that have safety function (as Krony suggested)

    Cheers
     
    Krony says thanks.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guest)

Share This Page