Good video cards for 350w pssu

[ViggyNash]

I have this relatively old 350w psu with 2 12v rails, one at 6a, the other at 12a. I'm pretty new to this and I don't fully understand how multiple rails work. As I understand it, I will effectively be running everything but the cpu on the 12a rail, and the cpu on the 6a rail.

I'm planning to get an i3 2100 which will just barely fit on the 6 a rail at 65w. I also have 2x 2g ddr3 and this mobo: http://www.newegg.com/Product/Product.aspx?Item=N82E16813157236

I'm not looking for anything game changing, just something that will run smooth with modest settings. I've been looking at the 6670, but I feel like that may be cutting it too close. Do you guys think my psu could handle a 6670 or would I have to downgrade?

Also, could someone explain multi-rail psu's? This entire question has been based on how I understand them currently so it could be that I'm asking the wrong question.

Lastly, would it be a better idea just to trash this psu and get a better one?

 

[panwala95]

if you want to keep your psu then your best bet would be getting a hd 7750
multirail means that in a single rail psu all the power is concentrated to just on rail
but in amultirail config power is distributed to two or more rails which is usually more efficent and lasts longer
on the downside in multirail configs till the time one rail is not fully loaded the other one will not be activated
also some manufactures like cooler master sometimes make false claims about their multi rail configs
if you are a casual gamer get the hd 7750 but if are more serious get abetter psu and probably a hd 7850
hope this helps!
good luck!

 

[fil1p]

Hey,

If you want to stick to that psu then you would be limited to a low profile card, such as the hd6670 you described. Now in total you only have 18 amps in total on your 12v rail, so you have effectively 216watts available, and that is cutting it close. Also what brand and model of power supply do you have? If you have a low quality one than you may run into problems. A good psu is the core of you pc and it is important to have a good one, there are many good brands like corsair, antec, seasonic, xfx, etc. If you want a card like the hd7770 or the hd 7750 then you need a 6 pin power connector and your psu as it is old and low power is unlikely to have one. If you have room in your budget, like $50 or so then you should be able to find a nice power supply. However if you only plan to run what you have and a hd 6670 then a 375watt psu may be enough as your system probably wont need more than 200watts. Also as for multiple rails, basically your simply distributing the power drawn from your components on seperate rails.

 

[panwala95]

Hey,

If you want to stick to that psu then you would be limited to a low profile card, such as the hd6670 you described. Now in total you only have 18 amps in total on your 12v rail, so you have effectively 216watts available, and that is cutting it close. Also what brand and model of power supply do you have? If you have a low quality one than you may run into problems. A good psu is the core of you pc and it is important to have a good one, there are many good brands like corsair, antec, seasonic, xfx, etc. If you want a card like the hd7770 or the hd 7750 then you need a 6 pin power connector and your psu as it is old and low power is unlikely to have one. If you have room in your budget, like $50 or so then you should be able to find a nice power supply. However if you only plan to run what you have and a hd 6670 then a 375watt psu may be enough as your system probably wont need more than 200watts. Also as for multiple rails, basically your simply distributing the power drawn from your components on seperate rails.

for a hd 7750 you dont need a pcie power connector
it works great from the power from the slot itself
some hd 7750s require power connectors which are overclocked

 

[ViggyNash]

Now in total you only have 18 amps in total on your 12v rail, so you have effectively 216watts available, and that is cutting it close.

So the difference b/w single and multi-rail psu's is only internal? And I can just look at the total amperage across both 12v rails and that's the amount of power available to the gpu, cpu, and any other pci cards?

As for the brand and model, it's a master power sku 333067: http://www.amazon.com/350-Watt-ATX-Power-Supply/dp/B000BM3ZN6 (this is just for reference, i already have it).

Also, what's the max power draw for a 7750 and for a 7770?

 

[djscribbles]

I would seriously consider a new PSU. If you already have the PSU in a system, keep in mind that it may not even be able to deliver it's rated power; pushing it to it's limit may result in you finding it's limit... (resulting in an exploded power supply and potentially damaged components.

The PSU design determines what wires are connected to which rail, and the total output isn't necessarily additive (it may be limited to less than a combined 18amps), if they have the 12A rail outputting to the CPU (which seems reasonable, since a 350W system is mostly going to be powered by the CPU), and they have a 6A rail wired to your HDDs, then your going to be in trouble. It's all in the sweaty sweaty hands of the guys who designed that PSU.

At the very least, you can replace that no-brand 350W psu with a no-brand 500W PSU for around 25$; while I don't, in any way, recommend doing that either, it should be slightly less risky.
Ideally, get something like this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139026

It maybe adding 50$ to your build, but throwing a firecracker PSU into your new PC may destroy the build anyway, putting you out more than 50$ for sure. It will also let you use a 7770 no problem.

edit: http://www.tomshardware.com/reviews/low-cost-psu-pc-power-supply,2862.html read this for some food for thought.

 

[fil1p]

for a hd 7750 you dont need a pcie power connector
it works great from the power from the slot itself
some hd 7750s require power connectors which are overclocked

Oops, i was looking at the 7870 and 7850, yeah the hd7750 does not require a 6pin connector, it does not even have a crossfire connector everything is done through the motherboard slot.

 

[fil1p]

Well when you add the amperage of both rails you get the total possible power output, so if you have 12amps on one rail and 6 on the other then you have a total of 18 amps available across your rails. That does not mean that each rail provides 18 amps, one provides 6 and the other 12. The hd7770 uses about 86watts and the 7750 uses 43 watts.
http://www.guru3d.com/article/amd-radeon-hd-7750-and-7770-review/7
^You can see te chart with power consumption in the link above.

However if you have room in your budget try to get a better psu, your psu does not provide much power and it is not of good quality. Although it should be enough to power your system I would still get a better one.

Hope this helps!

 

[djscribbles]

The two rails are not necessarily additive, there is typically a separate (but not always disclosed) value for the max combined output for the 12V rail; often there is an initial filtering stage before the two rails split off, and that stage can be limited to less than the total combined limits of the other two rails. (or at least that is my understanding).

 

[ViggyNash]

I've decided to trash this psu as you guys have provided plenty of good reasons to do so. Have any of you had experience with this psu? It's decently rated by the newegg community and it's relatively cheap.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817152028

 

[fil1p]

Well raidmax does not make the best psu's but its better than what you had. I would however not go with that one as people have had problems with raidmax before.

here are some good alternatives:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139027
^
That is a corsair builder series, its costs just unter $50 with a mail in rebate. Its not the best corsair has, but in your budget it will be a better alternative.

Look into PSU's from antec, corsair, seasonic for quality psus.

Hope this helps!

 

[ViggyNash]

I looked at the reviews for that corsair, and apparently it isn't what it looks like. Corsair supposedly cheaped out and switched from a platform made by seasonic to one made by CWT.

That said, I found this seasonic, and the only bad reviews it got was 2 fan/circutry issues.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151074&Tpk=N82E16817151074