Swift SF314-41 CPU stuck at 0.4 GHz all the time

piwakawaka
piwakawaka Member Posts: 4 New User
Hi, I've got a problem with my Swift 3 laptop and I've spent a couple of hours searching for a solution, to no avail.

I have a Swift SF314-41 (N17W7) which has a Ryzen 3500U CPU.

The problem started yesterday without any obvious changes (no Windows updates, no damage, no new software, etc) and is now happening 100% consistently.

The problem is that shortly after a boot, or shortly after waking from sleep, the CPU gets stuck at 0.4 GHz, no matter what I am doing. This makes everything run excruciatingly slowly. Using Task Manager > Performance I can see that the total CPU usage is never higher than 19%, and it's often flat-lined at 19% in the graph.

It happens for both battery and AC power supply.

If I put it to sleep then wake it up, it will run at up to about 2.6 GHz for around 20-30 seconds, then it gets stuck back at 0.4 and doesn't go up again.

I've tried the battery reset via paperclip method but that had no effect on the problem.

I've checked the BIOS for any fan readings, but didn't find any. Oddly I can't hear a fan and I'm not sure I've ever heard a fan running in this laptop. Does it even have one? No software I've tried seems to show a fan speed, and fan speeds are all missing from tools like HWMonitor, Notebook FanControl, and a few others.

CPU temperature according to HWMonitor is around 60-80 degrees, but since the CPU can't work harder than 0.4 GHz it doesn't really seem to warm up any more than that, so I'm wondering if I don't hear the fan simply because it's not getting hot enough. The CPU temperature sensor seems to be operational and sane.

I've checked my Power settings in Windows and the maximum CPU performance is set to 100% for both battery and AC power. Minimum was set to 0% but I tried raising that and it didn't seem to make any difference.

I'm sure the AC power supply is working because I can see the laptop charging normally when it's connected.

I'm at a bit of a loss about this! What could it be?

Answers

  • piwakawaka
    piwakawaka Member Posts: 4 New User
    Update: I've used an external fan and conduit to cool the CPU down to 30C, thinking maybe it's thermally throttling, perhaps due to a main fan failure, but even at 30C it's still throttling down to 0.4 GHz.
  • piwakawaka
    piwakawaka Member Posts: 4 New User
    Wasn't able to find a fix in the end - sent it back for repair.
  • Easwar
    Easwar Member Posts: 6,727 Guru
    Hi piwakawaka,

    Plz update us once the issue fixed. 
  • piwakawaka
    piwakawaka Member Posts: 4 New User
    @Easwar, as requested:

    I sent the laptop back to Acer who assessed it, found no fault (their report didn't even acknowledge my observations), reinstalled Windows, and sent it back (to the wrong address which took 6 weeks to resolve). It is working correctly now.

    Given I reinstalled Windows (& Linux) several times myself before sending it to them, I suspect it either got a sufficient amount of percussive maintenance during freight, or they have some kind of special hardware reset tool they used to clear the fault.

    Unfortunately if it happens again I am no further enlightened.
  • Easwar
    Easwar Member Posts: 6,727 Guru
    piwakawaka,

    Unit will have 90 days repair warranty if it happens with in the time limit you can claim for it.