[G4] power supply upgrade

[Richard Klein]

On Nov 12, 2006, at 8:07 PM, Charles Robles wrote:

> Hi guys, I am new here but i think i might be in the right place. I  
> recently purchased a mercury extreme 1.5 GHz processor upgrade for  
> my g4 originally 400MHz machine. I also previously installed an  
> extra hard drive and ati 9000 pro video card. The previous  
> processor upgrade was 800Mhz. Well, the new processor did not work-  
> no startup chime and no picture so i put back the old processor and  
> everything works fine. I received a replacement and got the same  
> results so i spoke to a tech guy where I bought it and he suggested  
> that I am probably right over the line powerwise. I suspect that he  
> might be right. He suggested I can get more power by buying a pc  
> power supply and just splice some wires and such to install it. I  
> don't know the details yet. I guess my question is do you think the  
> tech guy is correct as I suspect he is and what kind of pc alien  
> part should fit into the space and how big volt wise would be too  
> much for my g4 or should I just forget the whole thing?

I would guess that 350 watts should be the minimum rating you should  
consider.  There's some very good PC power supplies out there, but  
there's also some real crap, so stay away from brands you've never  
heard of.  I've personally been very happy with Antec power supplies,  
but some other reputable names to consider would be Thermaltake, PC  
Power & Cooling, and Enermax.  If you can afford it, overkill won't  
hurt anything (excess capacity is only used when it's needed, so a  
1000watt power supply in your Mac won't use any more electricity than  
a 350 watt one, except that the 350 watt supply will fail before your  
computer draws anywhere near the limits for the larger supply).  I'd  
place more priority on a reputable brand name than on the wattage  
rating, though.

I haven't taken the time to look at any wiring diagrams, but re- 
wiring the PC supply for your Mac should be pretty simple.  I'd like  
to do that myself, but my Mac's power supply isn't dead yet, and I've  
got plenty of other projects...  I *think* the external dimensions of  
the power supply will be the same, but a tape measure can verify  
that.  You can measure your own power supply, and you should be able  
to find dimensions for the PC power supply on the manufacturer's  
website.

Good luck!
-- Rich

Antec: http://www.antec.com/us/pro_powerSupply.html
Thermaltake: http://www.thermaltakeusa.com/product/Power/power_index.asp
PC Power & Cooling: http://www.pcpower.com/products/power_supplies
Enermax: http://www.enermax.com.tw/english/product_supply.asp