[vox-tech] Alert! Regulator failure.

[Jeff Newmiller]

On Wed, 12 May 2004, Karalius, Joseph wrote:

> I have a Dell Optiplex GX1 running sarge that completely freezes up every
> once in a while.  So I do a hard reboot and get "Alert!  Regulator failure."
> before the BIOS splash.  Only after a shutdown (power off) can I boot back
> up.  I can find confirmation of this problem out there on the overclocking
> sites, but still no real answers for a fix.  Anybody run into this before?
> Is this a fatal flaw in the motherboard? (mobo specs not available right
> now)  I was gonna start looking into a system upgrade anyway, but for the
> time being it would be nice to know what I'm up against here.

I am not an overclocker, but I work with electronics and electrical stuff
a lot.  From the description below, it sounds like certain processes may
be working the cpu and cache so hard that they draw enough current for
long enough to trigger the low-voltage watchdog circuitry.  I think it
would depend on the mobo/cpu combination as to which voltage regulator is
involved and just how low the voltage is going, but generally there are
bus voltage regulators and cpu voltage regulators.  BIOSs generally have
the option to increase the target voltages these days (and to change the
allowable variation in voltage?), but increasing the target voltages
increases your power dissipation which can cause the cpu to burn out if
you don't reduce your clock rate.  I suspect that the amount you would
have to increase it by to fix your problem would be small enough that this
really wouldn't be a concern... but you have to be aware of why you don't
want to go too far.  Letting the voltage go too low increases your chance
of data corruption, so you probably don't want to mess with that (if you
even can).

The description below describes the use of MMXCore operations as being a
known trigger for this kind of thing... since that is on the CPU die, one
might suspect the cpu voltage is the culprit... but MMXCore also makes
harsh demands on the transfer of data in and out of the cpu, so it could
be one or more of the external voltages.

Hope that helps...

> 
> Joey
> 
> http://www.adobe.com/support/techdocs/2256a.htm
> 
> The following clip is from the above link:
> 
> Additional Information 
> The electrical problem on the affected motherboards is triggered by computer
> operations that use the pathway (called a bus) between the processor and the
> RAM for an excessive number of microseconds. This problem can be triggered
> by the operating system or other applications; however, it often appears
> when using Photoshop or Photoshop Album because few other applications move
> memory as rapidly as Photoshop or Photoshop Album does. 
> In Compaq Presario notebook computers, either the electrical problem cited
> above or an overheated display card may cause the screen to turn black or
> the computer to restart.
> The electrical problem also occurs with Dell Optiplex GX1 computers and ASUS
> P2B-F and P3B-F motherboards and possibly with other motherboards.
> Background information 
> The electrical problem on the affected motherboards is triggered by computer
> operations that use the pathway (called a bus) between the processor and the
> RAM for an excessive number of microseconds. This problem can be triggered
> by the operating system or other applications; however, it often appears
> when using Photoshop or Photoshop Album because few other applications move
> memory as rapidly as Photoshop or process data as intensely as Photoshop
> Album during certain operations. For example, when Photoshop Album generates
> thumbnails while importing files, it uses the MMXCore extension
> (MMXCore.8bx) extensively. Because Photoshop Album requires more processor
> power when using the MMXCore extension, the usage may trigger an electrical
> problem on some motherboards.
> In Compaq Presario notebook computers, either the electrical problem cited
> above or an overheated display card may cause the screen to turn black or
> the computer to restart.
> The electrical problem also occurs with Dell Optiplex GX1 computers and ASUS
> P2B-F and P3B-F motherboards and possibly with other motherboards. 
> 
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> 

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