+12V Amperage

anbo369

anbo369

Member
hey,
my powersupply (Zalman ZM600-ST) has a max output of 30A on each of the +12V rails. If i am only using one of the rails does that mean it has a max output of 60A?

i'm running an Asus HD4850 which requires 30A i believe so that means that either way my PSU can handle it?

the reason i ask is that i got a blue screen while trying to play crysis (didn't even get to shoot anything, it happened just near the end of the opening movie)

thanks!
 
Yes, if you have multiple rails, you may add up the max output. 60A should be fine for a single HD4850.

Have you tried some other games? Do any others have problems? How about the PSU itself? Is it fairly new or does it have some age/hours on it?
 
well i built the computer (everything new) on New Years Eve so its not the age issue, Ir play DOW2 and some other older games that aren't even worth a mention lol.
i will have to try playing crysis again and see if it continues to happen.

thanks for the quick reply!
 
The_Other_One said:
Yes, if you have multiple rails, you may add up the max output. 60A should be fine for a single HD4850.

Have you tried some other games? Do any others have problems? How about the PSU itself? Is it fairly new or does it have some age/hours on it?
Click to expand...

On a multirail power supply you dont just add the rails, you take the total combined +12v rail wattage and divide it by the voltage to find the amperage(so wattage/12=amperage). The ZM600-ST for example has a total of 500W or 41.67A on the +12v rails, which is still plenty powerful for a 4850. (Its somewhat funny when you look at the amperage, 60A is like 720 watts on a 600W power supply), mainly the individual ratings are for max load on the rail, as many units dedicate +12v1 to the cpu.

For a BSOD,start with checking a few things:
Reseat and clean the contacts on the card
Check the temperature of the card
Reinstall video card drivers
Check power connections to the gpu(sometimes the 6pin connector isnt in tightly)
 
bomberboysk said:
On a multirail power supply you dont just add the rails, you take the total combined +12v rail wattage and divide it by the voltage to find the amperage(so wattage/12=amperage). The ZM600-ST for example has a total of 500W or 41.67A on the +12v rails, which is still plenty powerful for a 4850. (Its somewhat funny when you look at the amperage, 60A is like 720 watts on a 600W power supply), mainly the individual ratings are for max load on the rail, as many units dedicate +12v1 to the cpu.
Click to expand...
yeah what happens is that your PSU can't fully support running both rails at full load at the same time. So lets say you have two rails rated at 30a, it means that it can put out a max of 30a on one rail at a time, but it doesn't mean both rails can put out 30a at the same time. That's why the rated wattage on the 12v rail together is lower then the rated wattage of each individual 12v rail. Regardless, 40a should be fine. I'm thinking your BSOD is related to something other than your PSU.
 
I am running my 4850 on an off brand psu that supposedly has 860w of power and 36a on the +12v rail. you'll be fine with your zalman psu.
 
I just remembered something. Some guy told me this.

Think of PSU's as cars and trucks. Unbranded PSU is like a truck, has all the power but can't deliver it because of its weight. Branded PSU is like sport car, has the power and goes fast.
 
You must log in or register to reply here.
Back
Top