Is 36A on the +12v rail enough for a 4870?

yeah thats fine, i think that 32amp is recommended in a hi end rig for the 4870. So 36amp is fine.
As long as you dont plan on crossfire'ing two of them :P
 
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Depends on the unit itself tbh.... Plus is it a multirail power supply? If so you dont just add the rails together, you need to take total wattage over the +12v rails and then divide it by 12volts to get amperage.

If its anything cheaper or off brand, i wouldnt trust a dedicated gpu on it by any means.
 
bomberboysk said:
Depends on the unit itself tbh.... Plus is it a multirail power supply? If so you dont just add the rails together, you need to take total wattage over the +12v rails and then divide it by 12volts to get amperage.

If its anything cheaper or off brand, i wouldnt trust a dedicated gpu on it by any means.
Click to expand...

i had assumed he meant 32amp on that +12v rail
 
It's got 2 rails, but i'd assume that each 6 pin connector is on a different rail (even though they are on the same cable). here's a pic of the sticker:

101_0075-1.jpg


I'm still going lol over the 50 amps on the +5v :P

(by the way, we use 240v in Aus. Not sure if that affects the output in any way though)
 
That is more like 34a. You can't just add the 2 rails together and get the total. 4870 on the list below requires 34a.

Also for power requirements look at this.
http://www.computerforum.com/90110-power-recommendations-video-card.html

Which imo your getting to close for my personal comfort level of PSU over-power. If you max a cheap brand you run a chance it could surge and kill your entire system.


Also when you upgrade again buy a quality PSU like OCZ/Corsair a good example is your running a 860w PSU with 34a. I am running a 750w PSU with 60a. See the quality difference?
 
Cheap power supply, got most of its watts/amps. on the 3.3/5V rail. Its really probably around a 420/430 watts on the 12V rail. If it really could even put out 34 amps. on the 12V rail I would be surprised .
 
That's a horrible maximum rating for 12v rail for an 860watt powersupply. Heck, my CM Real Power Pro unit puts out 45 amps on the 12v rail and it's only 650 watts. I would seriously considering buying a quality unit before going ahead with any power hungry upgrades.
 
My A-Power had 15+16 amps on the 12v with 680w, which is pretty bad. and it was causing shutdowns in games.

I'll never be running two graphics cards, and it's not like i'm running 6 hdd's and 4 optical drives :P

My PSU isn't exactly high grade, but if i can run a 3870 i think i could run a 4870. All the newer models supposedly have lower power usage, correct?

I was on google and came across this:

http://www.vgaforum.com/showthread.php?t=21608

It shows that with the max wattage draw they can calculate the amperage, which they list as 13.75 amps load usage for the vanilla 4870 (no toxic edition, no overclock, no cf)

EDIT: I will be getting a decent power supply. maybe christmas or next year. I'm thinking a 600W corsair (hopefully modular)
 
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linkin93 said:
I was on google and came across this:

http://www.vgaforum.com/showthread.php?t=21608

It shows that with the max wattage draw they can calculate the amperage, which they list as 13.75 amps load usage for the vanilla 4870 (no toxic edition, no overclock, no cf)
Click to expand...

I don't trust a sticky that doesn't have user feedback from some forum I have never seen before. This COULD be deeply flawed and they never changed it. Then again they could be right. I wont risk my $800 rig over it.


linkin93 said:
EDIT: I will be getting a decent power supply. maybe christmas or next year. I'm thinking a 600W corsair (hopefully modular)
Click to expand...

Yeah at the price difference id get the TX750w Corsair (on sale for $90 currently)




In the end its your call though...but if God forbid something should happen I just want you not to blame me.
 
linkin93 said:
My A-Power had 15+16 amps on the 12v with 680w, which is pretty bad. and it was causing shutdowns in games.

I'll never be running two graphics cards, and it's not like i'm running 6 hdd's and 4 optical drives :P

My PSU isn't exactly high grade, but if i can run a 3870 i think i could run a 4870. All the newer models supposedly have lower power usage, correct?

I was on google and came across this:

http://www.vgaforum.com/showthread.php?t=21608

It shows that with the max wattage draw they can calculate the amperage, which they list as 13.75 amps load usage for the vanilla 4870 (no toxic edition, no overclock, no cf)

EDIT: I will be getting a decent power supply. maybe christmas or next year. I'm thinking a 600W corsair (hopefully modular)
Click to expand...
Doesnt matter the load...that is still a really low end unit.

Also, if the 6pins are on the same cable then logic dictates they are on the same rail. By ATX standards (usually) the +12v1 is set aside for CPU.

Lower power usage...hahahaha, GPU's have been sucking more and more power every generation now for god knows how long.
 
Ok so i've got the standard XFX 4870 1GB. Nothing done to it. All latest drivers (and all previous drivers removed) and it runs fine on all games which DO NOT use the Havok game engine. All games that do, the card shuts down after about 20 mins of playing. Far Cry 2, Wheelman and new Wolfenstein shut down after this time. The screen goes white, then blank and the sound stutters after a few seconds then the comp reboots! Boots up fine though. All other games (like Modern warefare 2, GRID, DIRT) work fine for over 3 hours. My PSU has not 6-pin PCIE cables, only 4 pin cables which i have used the converters on. One converter takes one 4-pin and makes it a 6-pin, the other takes two 4-pin and makes it into one 6-pin. Attched is a pic of my PSU as i cant understand what it all really means.
Image1071.jpg


Somebody please tell me if i can fix this as its getting quite annoying??
 
Your powersupply is inadequate. Get a decent 600w from a good brand (OCZ, Antec, Corsair, PC Power & Cooling, etc)

And you could have made your own thread. :)
 
Would an inadequate PSU cause it to only crash on games using the Havok game engine. (i can only assume its that as the only games it crashes on use Havok)?
 
You need a PSU with the proper 6 pin PCI-E connectors. adapters are bad news.
 
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That is a possibility. If so its still in warranty i believe.

I have fully up-to-date drivers.

2.6GHz Core 2 duo
2GB DDR2 RAM
1x250GB SATA HDD
1x500GB SATA HDD
1xCD-DVD rom drive
 
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