First of all i'd like to say that i am portuguese and my english is quite far from being the best.
What bring's me here today (besides this forum reputation) is the fact that i have recently upgraded my system from a 775 socket to a i7 CPU, the cpu is a i7 920 with 3x2GB memory at 1600Mhz with Cl8 (corsair xms3) and a Gigabyte EX58-UD3R and i have been thinking about upgrading my video card as well, i've cosidered buying a GTX295 for 420 euros (595.54$) wich seems a little expensive but it is a really charming graphics card to say the least, but then, after spending a few hours watching a lot of reviews i noticed that two GTX260 can in most cases keep up with a GTX295 even surpassing it sometimes, even though a GTX295 incorporates two GTX280 (if i'm not mistaken). Well, two GTX260 comes a much less coin than a GTX295 since i can get each one for around 160 euros costing me 320 euros to get practicaly the same performance i'd had with a gtx295 only 100 euros cheaper that i could really use to get a really nice coller for my CPU that looks more like a toaster with the stock coller. The problem is, that i have a crappy Nox pulsar 750w that i bought for a very badly spent 120 euros (170.15$), the most stupid thing about it is that i coulded have grabed a CORSAIR HX-750W only for more 10 euros but this Nox looked great (aesthetically ) besides it was more than enough for the pc i had by then. But enough drama, the question is can this Nox pulsar 750w take two GTX260? It has a combined 55amp at +12v. I was thinking about getting two pre clocked GTX260.
I would if i could... but i bought it at more than year ago.
if it's rated amperage is true then it can support dual GTX 260's, although it's more like a 700w PSU than a 750w.
That's what i think too, but even if it can power two GTX260 i don't think it will be much of it left to power the rest of my PC such as the CPU, BOARD and RAM, that's why i mentioned them in my first post.
I cannot say anything about the quality (simply unfamiliar with the brand) but 55 amps will have no problems powering two GTX260's. A pair of them will only pull about 24 amps. 10 amps for an OC'd CPU will leave you 20 amps for the rest of the system. This all depends on the PSU being able to provide that 55 amps.
Here is how you can tell. If while gaming - and only gaming, you start getting seemingly random reboots, that is one sign of inadequate power problems. Simply remove one video card. If the problems go away, that is a pretty good indication that that you did have power problems.
The only problem with this is that video driver problems can cause the same symptoms.