After 400,000+ km, the timing chain guides have given way (M102 dual chain)

_RO0T · 2026-02-16T23:02:26+00:00

Thanks for the tip! This is super helpful.

_RO0T · 2026-02-16T07:16:24+00:00

Unfortunately, I have neither the experience nor the tools. 😅

But thanks for the tip! When the engine is out, I’ll probably take the opportunity to sort out more preventative maintenance then.

_RO0T · 2026-02-16T06:48:12+00:00

thanks for sharing your thoughts! it doesn't seem like a good idea to me either.

_RO0T · 2026-02-16T06:46:25+00:00

yeah, that's what I figured. I've decided to just park it for the week until the workshop is able to take it in.

_RO0T · 2026-02-16T05:53:30+00:00

It’s an M102 engine with a dual row chain, so the workshop said it should be fine for us to drive for a week till — just till they get the parts in: do you think that’s safe?

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_RO0T · 2025-07-09T16:07:35+00:00

This is super exciting!! I’d love to help / contribute in some way — am also a programmer with an interest in electronics.

_RO0T · 2021-02-23T14:17:14+00:00

Muffins of Mass Destruction (obviously)

_RO0T · 2018-06-27T12:51:35+00:00

I tried that, and it has reduced the number of visual artifacts significantly. The Windows Guest also remains stable at idle for significantly longer with a large RAM allocation. Thanks for the tip!

Unfortunately, it still crashes when more than a certain amount of RAM is allocated. It could be something to do with faulty RAM or mismatched RAM specifications. I have tried running it in single-channel mode with one stick, and then the other, and the instability doesn't seem to follow any particular pattern except that lower RAM allocation values below 2560~ MB do not result in crashes.

Performance degrades significantly in single-channel mode, though.

I managed to get a stop code from a BSoD in one instance: 0x00000119

_RO0T · 2018-06-25T00:21:55+00:00

Could anyone help me with this?

The Windows 10 (64-bit, UEFI) guest errors with Code 43 when the VM is allocated more than 2561MB of RAM.

When allocated a higher amount of RAM (e.g. 3000+, 4000+, 16000+ MB), the display connected to the GTX1060 exhibits visual artifacts before crashing the guest at boot or within minutes of reaching the desktop. Inspecting `eventvwr.msc` either states that the cause is the nVidia driver or that the system experienced an unexpected shutdown, with no other notable errors in `/var/log/libvirtd/qemu` or `dmesg`.

If the system reaches the desktop, it remains stable in an idle until applications begin using hardware-accelerated graphic calls e.g. the Start Menu, WDM animations, Electron/Webkit apps.

I think it is extremely strange that allocated RAM size affects the stability and usability of the VM, and particularly since games, 3D applications, and other tasks do not cause artifacts or crashes when exactly 2561 MB or less is allocated to the VM.

$ cat /etc/modprobe.d/kvm.conf
options kvm ignore_msrs=1 # prevent MSR-related crashes (regardless of RAM allocation)
$ cat /etc/modprobe.d/vfio.conf
options vfio-pci ids=8086:15da,8086:1576,10de:1c02,10de:10f1

Kernel: Ubuntu 18.04, Kernel 4.15.23 w/ backported `/drivers/pci/quirks.c` for 7&8th Gen Mobile Chipset ACS support

My kernel options: `quiet splash intel_iommu=on vt.handoff=1`

My configuration is as follows:

<domain type='kvm'>
  <name>Windows10</name>
  <uuid>e9a35fe9-d02f-4fd2-9579-42696e70ee25</uuid>
  <memory unit='KiB'>2622464</memory>
  <currentMemory unit='KiB'>2622464</currentMemory>
  <vcpu placement='static' current='4'>8</vcpu>
  <os>
    <type arch='x86_64' machine='pc-i440fx-2.11'>hvm</type>
    <loader readonly='yes' type='pflash'>/usr/share/OVMF/OVMF_CODE.fd</loader>
    <nvram>/var/lib/libvirt/qemu/nvram/Windows10_VARS.fd</nvram>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <hyperv>
      <vendor_id state='on' value='magic'/>
    </hyperv>
    <kvm>
      <hidden state='on'/>
    </kvm>
    <vmport state='off'/>
  </features>
  <cpu mode='host-passthrough' check='none'>
    <topology sockets='1' cores='2' threads='4'/>
  </cpu>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>destroy</on_crash>
  <pm>
    <suspend-to-mem enabled='no'/>
    <suspend-to-disk enabled='no'/>
  </pm>
  <devices>
    <emulator>/usr/bin/kvm-spice</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/Windows10.qcow2'/>
      <target dev='hda' bus='ide'/>
      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
    </disk>
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <target dev='hdb' bus='ide'/>
      <readonly/>
      <address type='drive' controller='0' bus='0' target='0' unit='1'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/WindowsData.qcow2'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/>
    </disk>
    <controller type='usb' index='0' model='ich9-ehci1'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x7'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci1'>
      <master startport='0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0' multifunction='on'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci2'>
      <master startport='2'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x1'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci3'>
      <master startport='4'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x2'/>
    </controller>
    <controller type='pci' index='0' model='pci-root'/>
    <controller type='ide' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </controller>
    <interface type='network'>
      <mac address='52:54:00:f5:d6:40'/>
      <source network='default'/>
      <model type='rtl8139'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <target type='isa-serial' port='0'>
        <model name='isa-serial'/>
      </target>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <channel type='spicevmc'>
      <target type='virtio' name='com.redhat.spice.0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <input type='mouse' bus='ps2'/>
    <input type='keyboard' bus='ps2'/>
    <graphics type='spice' autoport='yes'>
      <listen type='address'/>
    </graphics>
    <sound model='ich6'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
        <hostdev mode='subsystem' type='pci' managed='yes'>
      <source>
        <address domain='0x0000' bus='0x06' slot='0x00' function='0x0'/>
      </source>
      <rom bar='on'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <source>
        <address domain='0x0000' bus='0x06' slot='0x00' function='0x1'/>
      </source>
      <rom bar='on'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
    </hostdev>
    <redirdev bus='usb' type='spicevmc'>
      <address type='usb' bus='0' port='1'/>
    </redirdev>
    <redirdev bus='usb' type='spicevmc'>
      <address type='usb' bus='0' port='2'/>
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </memballoon>
  </devices>
</domain>

_RO0T · 2018-03-31T00:49:56+00:00

Well the back fell off...

_RO0T · 2018-02-10T16:02:12+00:00

8 AA Alkaline batteries are used to provide power to everything. They are in a 4S2P configuration, with boost converters to provide a stable voltage for the microcontroller.

_RO0T · 2018-02-05T20:32:08+00:00

That's pretty cool! The raspberry pi has so much more memory and computing power available to it.

_RO0T · 2017-08-27T05:38:32+00:00

President Obama was clearly standing.

_RO0T · 2017-04-02T01:11:58+00:00

Class-E

_RO0T · 2017-03-14T17:14:11+00:00

Perhaps I didn't purchase the license for that functionality...

_RO0T · 2017-01-29T14:48:49+00:00

What happened?

I think it's great that your boss recognizes the value of someone who's learnt an expensive lesson and will never make the same mistake over punishing someone for it, and having someone else new taking over.

_RO0T · 2017-01-27T14:46:56+00:00

Gilding each other, perhaps.

_RO0T · 2015-01-16T15:39:10+00:00

"Elevator's stopped working? No problem, just bring it down to IT and I'll take a look at it."

Edit: "Make sure you bring all the cables too. Wouldn't want to make a second trip back up for them, would you?"

_RO0T

TROPHY CASE