R7 270x underclocking

B_S

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Mar 3, 2014
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Is it possible to underclock a graphics card like R7 270x?

The 270x requires 2x 75watts (6-pins), and need more Wattage than the R7 270.
I have a PSU, but not sure how many Watts it produces, or rather how many Ampere it produces over the 12V line.

If it doesn't produce enough for the 270x, I could buy a new PSU. But I wanted to test first.
So, what if I buy this card, and the PSU doesn't provide enough power? Could I make the card draw less power by underclocking it?

Also what if I only have one and not 2x 6-pins? Could I still plugin just the one? Or will the computer not boot up then? I mean will the card still work but at lower performance?

 
I will be able to check that probably later today. But if it doesn't have enough it's good to know that number, 24A, when i'm comparing PSUs to buy.

How does it work with the rest of the power your system needs, like CPU, motherboard, case fans and so on. Do these also draw their power on the 12V line? Or it's the 3.3V, 5V?
 
gpu - cpu are the two most energy hungry pc components and they draw from the 12v rail! the 24v recommendation refers to the system not only the gpu, so incase you need a psu upgrade consider these http://pcpartpicker.com/part/evga-power-supply-100b10500kr a good one and http://pcpartpicker.com/part/xfx-power-supply-p1550sxxb9 a really good one seasonic made which can support a gpu upgrade like R9 280x or gtx770 plus o/c actually even a 450w psu would sufice but its always good to leave a bit of a headroom, cause running a psu on its limits isnt such a good idea.!
 
Those look good.
I have been comparing XFX Core 550W or 650W, or alternatively the Zalman ZM450-GS 450W.
I should say, i'm in Sweden so those are the cheapest one's i've found that also gets good reviews. They're like tier 2 (or almost tier 1) PSUs i think.

I'm a bit undecided on system specs. Almost decided on a Sapphire 270x. The 280x would be out of budget for me.
I'm also almost decided on a Intel CPU, the i3-4130. The alternative is buying an AMD FX-6300 and overclocking.

Are there any other components that draw from the 12V rail?
For example I can hook the case fans to the CPU fan connection? Would that also be on the 12v?
 
The 550W Core is rated 44A on one 12V rail. The 650W 53A on 12V.

The Zalman has two 12V rails. One rated 21 A, the other 18 A. Would that be enough for the Intel build with the 270x?

And I'm pretty certain the old PSU I was talking about won't be enough.
 
zalman zm is good and with total 39A combined power would be sufficient. fans consumption is very low and neglegible, hook up as many as you can.! an good air flow can be achieved with couple as intake in the front and an exhaust at the back. you dont need a dosen of them.also isnt SUPER FLOWER psu aveliable in your region?they have some pretty good units too.!
 
Yes they are! Some different models.

Super Flower SF500P-12P 500W:

http://www.prisjakt.nu/produkt.php?rec=856950

It's the same price range as the XFX and Zalman.

I haven't put together a computer before. Using two 12V rails like the Zalman uses, is one connected to the Graphics card, and then the other to the mobo? So 18A is enough to power the graphics card while 21A is enough for CPU and motherboard?
 
as i mentioned erlier the power is combined 39x12=468W and is distributed depending the needs.there isnt any component connected to only one rail. both rails are avaliable. there are specific cables for mobo, cpu and gpu. a 24pin for mobo a 4 +4 pin for cpu and 4 or 6 or 6+2 for gpu depending model.dont worry it wont be difficult.
 
The hexa-core 8320 would be better, but it's more expensive.. Although i'm sure good value. So you think 450w is enough for the 8320? If I get AMD I would probably want to overclock.