Looking to replace the ATX PS in my p3 dual Voodoo 2 rig, it’s currently pulling around 115watts according to my kill-a-watt meter, when playing a game with SLI. Looking at a new PS with the following specs. Will this cut it too close on 5V or is there some math I’m missing?
What are the specs of your current PSU (efficiency-wise especially) ? If it is an older unit that predates 80+ ratings, it may may well have an efficiency of 60 to 70 % (depending on load).
EDIT : What I mean to say by that is that 115 watts being drawn for the outlet includes waste energy (heat), whereas the values on a PSU's label refer to effective usable power (not including waste energy).
I’m using this POS now, circa 2006 maybe.
Chadti99 wrote on 2021-05-10, 17:52:I’m using this POS now, circa 2006 maybe.
According to http://www.apextechusa.com/products.asp?pID=44 , that thing's efficiency is around 65% at full load (likely significantly less at the load your system is drawing). That means that, at best, assuming 65% efficiency (very optimistically), that 115W at outlet means the PSU is actually providing 74.75 watts (0.65*115W) . Even if that 74.75 watts was all coming from the 5V rail (it obviously isn't), that would mean about 14.95A (74.75W/5V) being drawn from that rail .
In other words, that new PSU is probably adequate assuming
a) it is a quality unit and those ratings are true (feel free to specify brand/model)
b) that the 115W at outlet draw is truly representative of the PC running at max load
Thanks for the detailed response! I’m looking at this guy:
EVGA 550 B5, 80 Plus BRONZE 550W, Fully Modular, EVGA ECO Mode, 5 Year Warranty, Compact 150mm Size, Power Supply 220-B5-0550-V1 https://www.amazon.com/dp/B084RGH8W4/ref=cm_s … GZS0HB2F1V5N0GZ
Yeah, the new one should work fine.
I really doubt that old power supply could actually supply anywhere near the specified power. It is probably more of a 300-350w power supply if you are lucky.
It would probably catch fire or at least die fantastically if put under a load that is specified. How I miss the [H]ardOCP power supply reviews.
cyclone3d wrote on 2021-05-10, 23:35:It would probably catch fire or at least die fantastically if put under a load that is specified. How I miss the [H]ardOCP power supply reviews.
Yah the main reason I’m replacing is that I think I’ve come dangerously close to just that.
Yay, a loose Molex connector. Have to make sure to use a small screwdriver to squeeze the female connector tighter. Even better is releasing said connector from the socket and using a pliers to squeeze it tighter. Loose connections do bad things because then you have high resistance and it heats up too much.
But since you are replacing it I guess it is pointless.
