AMD Athlon Buyer's Guide - Part 4: Power Supplies

How can you tell if your power supply is the cause of your Athlon’s instability?  There are a number of warning signs, but keep in mind that unless you are using components that are 100% Athlon compatible (memory is often a cause of instability, be sure to get a guarantee from your vendor that the memory you’re purchasing has been tested to work on the current crop of Athlon motherboards) the cause of your problems could be anything. 

Provided that you do eliminate most of the variables, here are a couple of warning signs that we’ve encountered with Athlon systems where the power supply was not supplying enough power to the system:

• System will not POST (no video on the screen), but the CPU, motherboard, memory and video card test out fine on another Athlon setup.  Try sticking in a lower clock Athlon (i.e. Athlon 500) and see if the system boots up, if it does, then check the +5V and +3.3V ratings on your power supply, it may not be able to provide enough power for the higher clock speed Athlon.
  
  
• System crashes immediately upon entering in a 3D game/application where the AGP 3D accelerator is being used.  This problem is commonly associated with the inability of the power supply and maybe even the motherboard to deliver enough power to the graphics card in the AGP slot.  This is because the CPU is drawing too much power from the 3.3V rail for the AGP card to operate properly when it’s being stressed even a little.  To try and see if the power supply is actually the culprit try lowering the core clock of your graphics card and see if that helps.
  
  
• Random crashes/lockups during normal use, all other components are recommended/certified for use with the Athlon and the system is setup on a clean install of the OS with all appropriate drivers installed and patches applied.  First you’ll want to check to make sure that your heatsink/fan is properly mounted onto your CPU and that cooling is not an issue (try running the system with the case open, see if that helps, if it does then the problem may be heat related).  If it turns out that the problem isn’t related to the Athlon getting too hot then it may be that the power supply isn’t able to provide the system as a whole or the CPU itself with enough power, causing the system to lock up. 

This is obviously not a comprehensive list of warning signs, but the above three are some of the most common.  Don’t be so quick to blame the Athlon platform for stability problems, after all, AMD is running their website off of Athlon and K6-III web servers.  We have been running Athlon systems in lab with stability similar to that of their Intel counterparts.  The CPU is definitely capable of running in a stable environment, you just need to be a bit more careful with what components you use, especially when it comes to power supplies. 

There are a number of power supplies out there that simply carry a different name but are actually identical to another unit.  In an attempt to help clear up some confusion, here are a couple of the notable units:

Fortron/Source is actually Sparkle Power International LTD.  While the model numbers differ, the units are the same.  Fortron/Source’s FSP300-60GN is identical to SPI’s FSP300-GT, both are 300W units and both have the same +5V, +12V, and + 3.3V ratings. 

Powmax is actually Leadman Electronic.  Leadman manufactures their power supplies, including those on the recommended list, under the Powmax name. 

Fong Kai Industrial’s ATX-250-1 can also be found under the Enlight name, the ratings are identical.