I have an hec Ace Power 580W psu that "supports SLI," and I really need help in figuring out if it has enough 12v amps to power this system:
Crossfired pair of Sapphire Radeon HD 3870s
Intel E7200 wolfdale cpu
1 SATA hdd
1 DVD-RW/CD-RW drive
4 ddr2800 dimms (voltage- 1.9v to 2.1v)
4 non-LED fans
1 PCI network card
From the specs on the psu box, the company only lists the combined power of the 3.3v and 5v rails (@240W). Following the same calculations in this thread for estimating the 12v combined wattage (http://www.tomshardware.com/forum/234600-28-calculate-rails), my psu should provide around 37.96 amps:
580W minus (-12v*1A) minus (+5Vsb*2.5A) minus (100W of combined 3.3v and 5v power) divided by 12v = 37.96 amps @ +12v.
*the steps from the thread stated that the 3.3v and 5v combined typical load should be around 100W, so 100W was subtracted from the total wattage instead of the listed 240W - the psu in the thread had the same combined 3.3v and 5v power as mine)*
Unfortunately, the psu box doesn't show which 12v connectors are from which 12v rail. How can I tell which of my two PCI-express 6pin connectors are attached to which rail, and if my dual rail psu follows the ATX standard? If my dual 12v rail psu does follow the ATX standard (with +12V2 dedicated only to the CPU), is there any possible way I could balance the load of my cards evenly onto both rails so as not to reach the current limit?
One last thing (sorry!) - according to my video card box, a 550W psu with 38 amps on the 12v rail is "recommended". Should the system I'm planning work alright with my 550W psu with 37.96 amps?
Thanks for your help, and I apologize in advance if I'm not making any sense - I've been desperately combing the net for info for the last couple of hours.
Crossfired pair of Sapphire Radeon HD 3870s
Intel E7200 wolfdale cpu
1 SATA hdd
1 DVD-RW/CD-RW drive
4 ddr2800 dimms (voltage- 1.9v to 2.1v)
4 non-LED fans
1 PCI network card
From the specs on the psu box, the company only lists the combined power of the 3.3v and 5v rails (@240W). Following the same calculations in this thread for estimating the 12v combined wattage (http://www.tomshardware.com/forum/234600-28-calculate-rails), my psu should provide around 37.96 amps:
580W minus (-12v*1A) minus (+5Vsb*2.5A) minus (100W of combined 3.3v and 5v power) divided by 12v = 37.96 amps @ +12v.
*the steps from the thread stated that the 3.3v and 5v combined typical load should be around 100W, so 100W was subtracted from the total wattage instead of the listed 240W - the psu in the thread had the same combined 3.3v and 5v power as mine)*
Unfortunately, the psu box doesn't show which 12v connectors are from which 12v rail. How can I tell which of my two PCI-express 6pin connectors are attached to which rail, and if my dual rail psu follows the ATX standard? If my dual 12v rail psu does follow the ATX standard (with +12V2 dedicated only to the CPU), is there any possible way I could balance the load of my cards evenly onto both rails so as not to reach the current limit?
One last thing (sorry!) - according to my video card box, a 550W psu with 38 amps on the 12v rail is "recommended". Should the system I'm planning work alright with my 550W psu with 37.96 amps?
Thanks for your help, and I apologize in advance if I'm not making any sense - I've been desperately combing the net for info for the last couple of hours.