Is there such a thing...

I tallied up what my system draws right now, this is what I've got;


DVD = 5v/1.5a 12v/2.0a
HDD (160GB)= 5v/.92a 12v/.90a
HDD (60GB)= 5v/.80a 12v/.45a
CPU = 5.4a (65w)
3x case fans totaling approx. 4w
---
148w before the 7600GT, is my 7600GT really going to use that much power? 100w??

My current PSU only has 15a on the 12v rail.. is the 7600GT really using the rest?

If not, I have to wonder why I've been getting freezes whenever I try to install COJ

EDIT: That Hipro you recommended me only has 14a and 15a on the 12v rails.. I need at least 18a
 
oscaryu1 said:
14+15A = 29A, more than enough...

Its dual rail...
Click to expand...

I'm well aware that it's dual rail, but my research has told me that dual rail doesn't mean I'll get Rail1+Rail2 output, I'm under the impression that it divides the power between certain cables... correct me if I'm wrong, but please provide proof as the research I've done hasn't turned up facts, only opinions on other forums.
 
..should I assume that 12v1 and 12v2 work together to provide a total output of 29a, or do the rails split their output between certain connections..?
 
I just ran into another problem with onboard video and went through and tested my connections and cables.. turns out I had a bad IDE cable.. Call of Juarez is now installing fine!

Hopefully I won't need a new PSU just yet, but I'll be looking into that Hipro soon.. :D
 
Glad you got it sorted. With regards to the dual rail issue, there's little that should be open to opinion. For any complaint design, one 12V rail (+12V2) will power the CPU, the other rail (+12V1) will be responsible for powering everything else (you can confirm that by reading the ATX spec at www.formfactors.org, if you're so inclined). In some cases, PSU manufacturers won't follow this specification rigidly, and you might have a PCI-E connector, for example, placed on the same rail as the CPU, but that's the exception rather than the rule.

Using your example and figures(which are a little off, but not enough to make a difference),
+12V2 = ~3.5A (HDDs + Optical + fans) + ~3A (7600GT) = 6.5A
+12V1 = 5.4A (CPU)

You can see that your quite safe with a dual rail PSU such as the Hipro. Moreover you can see that by splitting the load over two +12V rails, you don't need any single rail to be as big, which is a large part of the idea behind dual rails.

Now let's make things more complicated...
You can see in my recommendations list, I've listed a total capacity next to the individual +12V outputs, which in most cases is not the sum of each individual rail. This is because while each 12V rail is separated from the other, they're almost always fed by the same transformer and other circuitry, which has its own limitations. Thus, while you may be able to draw up to 14A on +12V1 and 15A on +12V2, you can't necessarily draw 14A on +12V1 and 15A on +12V2 at the same time. The total capacity is a little less than the 29A that adding the rails would imply (and, for some PSUs, markedly less). A lot of people either don't understand this, or choose to ignore it for simplicities sake.

If you find all this confusing, you're not alone. Fortunately, video card manufacturers don't expect users to understand the specifics of their rail implementation, and that's why that just quote the total figure.

18A doesn't mean 18A on any individual rail, it means 18A in total over all the +12V rails. A unit like the Hipro easily exceeds that.
 
ceewi1 said:
Glad you got it sorted. With regards to the dual rail issue, there's little that should be open to opinion. For any complaint design, one 12V rail (+12V2) will power the CPU, the other rail (+12V1) will be responsible for powering everything else (you can confirm that by reading the ATX spec at www.formfactors.org, if you're so inclined). In some cases, PSU manufacturers won't follow this specification rigidly, and you might have a PCI-E connector, for example, placed on the same rail as the CPU, but that's the exception rather than the rule.

Using your example and figures(which are a little off, but not enough to make a difference),
+12V2 = ~3.5A (HDDs + Optical + fans) + ~3A (7600GT) = 6.5A
+12V1 = 5.4A (CPU)

You can see that your quite safe with a dual rail PSU such as the Hipro. Moreover you can see that by splitting the load over two +12V rails, you don't need any single rail to be as big, which is a large part of the idea behind dual rails.

Now let's make things more complicated...
You can see in my recommendations list, I've listed a total capacity next to the individual +12V outputs, which in most cases is not the sum of each individual rail. This is because while each 12V rail is separated from the other, they're almost always fed by the same transformer and other circuitry, which has its own limitations. Thus, while you may be able to draw up to 14A on +12V1 and 15A on +12V2, you can't necessarily draw 14A on +12V1 and 15A on +12V2 at the same time. The total capacity is a little less than the 29A that adding the rails would imply (and, for some PSUs, markedly less). A lot of people either don't understand this, or choose to ignore it for simplicities sake.

If you find all this confusing, you're not alone. Fortunately, video card manufacturers don't expect users to understand the specifics of their rail implementation, and that's why that just quote the total figure.

18A doesn't mean 18A on any individual rail, it means 18A in total over all the +12V rails. A unit like the Hipro easily exceeds that.
Click to expand...

I think I understand, and appreciate the well written explanation, though I took my figures directly from the labels on my components so I think they're correct.

In any event, I'll pick up the Hipro sometime in the next couple of weeks.. I've got to get some bills paid off now that I know I don't need a new PSU just yet :o

Thanks again for the advice and explanation :D
 
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