GPU/PSU woes part ii

[dodonpachi]

Hi, a while ago I posted asking whether my current PSU - Antec EarthWatts 500W - would be up to the job of powering a R9 280 safely. I was advised that since it's an okay quality, if ageing unit I should be alright.

I bought an ASUS R9 280 DirectCU II which has 1 x 8 pin and 1 x 6 pin connector. My PSU only has 2 x 6 pin connectors, am I okay plugging the 2nd 6 pin into the 8 pin slot? Will I be providing enough power? I know that 8 pin connectors have the potential to provide more power but that is the extent of my knowledge. Will the supplied 6 to 8 pin adaptor make any difference to just plugging the 6 pin straight in....

Okay, so trying it the 6 pin into the 6 pin slot gives me a green led on the connection - the other 6 pin pci - via 6 to 8 pin adaptor gives me a red led on its connection, is there anything to be done? does the 2 x 6 pin to 1 x 8 pin adaptor need both to be powered to work?

Thanks

 

[crimsonyoshi]

Short answer - no. If the card has pins for a 6 and 8 slot, every one needs to be filled properly.

In terms of 6 to 8 pin adapter, unless you're supplying additional power via an active adapter (if those even exist for PSU's), you're distributing 6 pins of power over 8, so all 8 pins receive less power individually. There may be some newer PSU's out there that detect how many pins are actually at the end of the wire, and adjust accordingly (I'm no expert in the PSU field).

Safest and best bet would be to grab a PSU that has the right number of pins - no adapters.

 

[Dangman]

Hi, a while ago I posted asking whether my current PSU - Antec EarthWatts 500W - would be up to the job of powering a R9 280 safely. I was advised that since it's an okay quality, if ageing unit I should be alright.

I bought an ASUS R9 280 DirectCU II which has 1 x 8 pin and 1 x 6 pin connector. My PSU only has 2 x 6 pin connectors, am I okay plugging the 2nd 6 pin into the 8 pin slot? Will I be providing enough power? I know that 8 pin connectors have the potential to provide more power but that is the extent of my knowledge. Will the supplied 6 to 8 pin adaptor make any difference to just plugging the 6 pin straight in....

Okay, so trying it the 6 pin into the 6 pin slot gives me a green led on the connection - the other 6 pin pci - via 6 to 8 pin adaptor gives me a red led on its connection, is there anything to be done? does the 2 x 6 pin to 1 x 8 pin adaptor need both to be powered to work?

Thanks

In Asus' case, yes, you need to connect both the 2 x 6Pin to the 8Pin adapter. Which technically means you would need a total of three six-pin connectors on the PSU. .......which your PSU doesn't have. Normally, most GPU manufacturers would include a molex to 8 Pin (or 6Pin) PCI-E power adapter for free but apparently Asus did not want to in this case.

Well here's what you can do:
1) Return that Asus card and get a MSI, XFX, or Gigabyte R9 280 cards as those will have the necessary adapters that you need

2) Get a new PSU like the Seasonic SSR-550RM 550W PSU

3) Buy a molex to 8 Pin PCI-E adapter that looks like this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16812400034

Make absolute sure that it says "8 Pin PCI-E" on the molex adapter as there's also the 8Pin EPS12V CPU connector as well. You don't want to get the two mixed ujp.

 

[dodonpachi]

Thanks for the replies.

In the meantime I (perhaps foolishly) connected the 2nd PSU 6pin to the other connector on the 6 to 8 adapter and the graphics card then displayed 2 green LEDS. The two 6 pin connectors on the adapter are wired slightly differently, one has a brown wire as well as the yellow and black, I originally tried this one, when I connected via the one that only has black and yellow wires the card seemed happy.. I've played a few games with it running this evening... Is this very ill advised?

Danny, that Seasonic doesn't seem that readily available in the UK, is there anything else you would recommend? I think I read someone here suggest an XFX that is a re branded Seasonic, would that be worth looking at?

 

[Dangman]

Thanks for the replies.

In the meantime I (perhaps foolishly) connected the 2nd PSU 6pin to the other connector on the 6 to 8 adapter and the graphics card then displayed 2 green LEDS. The two 6 pin connectors on the adapter are wired slightly differently, one has a brown wire as well as the yellow and black, I originally tried this one, when I connected via the one that only has black and yellow wires the card seemed happy.. I've played a few games with it running this evening... Is this very ill advised?

Let me get this straight: The video card is only getting power from that single 8 Pin adapter which has two 6Pin PCI-E power connected to it. Correct? If so, not a good idea AFAIK.

Danny, that Seasonic doesn't seem that readily available in the UK, is there anything else you would recommend? I think I read someone here suggest an XFX that is a re branded Seasonic, would that be worth looking at?

Which UK online computer hardware store will you be buying from?

Virtually every XFX PSU is a rebranded Seasonic however some of those XFX PSUs either use lower quality parts or have lower standards than Seasonics or based on older Seasonic designs.

 

[dodonpachi]

Hi - I can see how this got confusing, thanks for your patience.

http://i.imgur.com/sDeTigg.jpg

On the left, the 6 pin from the PSU going into the 6 pin on the GPU, on the right the only other PSU 6 pin, going into one end of the adapter and then into the GPU 8 pin connection.

By the SSD: the other end of the adapter, this end has an extra brown wire and caused the GPU led to go red when I tried it.

Is what I am doing dangerous?

I would get a new PSU if required from Amazon ideally, although Ebuyer, Overclockers, Scan are fine. Scan are the only place that seem to have that Seasonic, it's 74 pounds, do I need to spend that much? I don't care about it being modular particularly but ultimately will go for what you say is that best quality option.

 

[Armenius]

You should only need one of these inline 6-pin to 8-pin PCI-E adapters. Then you can plug one of the 6-pins to the 6-pin on the GPU and use the adapter on the other 6-pin to the 8-pin on the GPU. 6-pin PCI-E has 3 leads and 3 grounds, which allow 2.08 amps per lead for 75W total. 8-pin simply adds 2 more grounds, which allows each lead to handle double the current at 4.16 amps for 150W total.

 

[Dangman]

Is what I am doing dangerous?

To be honest, I'm not quite sure. Armenius is right that a single 6Pin to 8Pin PCI-E adapter is all that you really need. However, I'm not sure if the included Asus adapter is actually fully capable of just a single 6Pin to 8Pin connection.

Did you read the manual?

I would get a new PSU if required from Amazon ideally, although Ebuyer, Overclockers, Scan are fine. Scan are the only place that seem to have that Seasonic, it's 74 pounds, do I need to spend that much? I don't care about it being modular particularly but ultimately will go for what you say is that best quality option.

You could go with this Antec High Current Gamer PSU instead:
http://www.overclockers.co.uk/showproduct.php?prodid=CA-147-AN&groupid=701&catid=123&subcat=1088

 

[dodonpachi]

Thanks for all the help... I will go for the 6 to 8 adapter for now and shortly get a new PSU. I am at the point where I almost have enough old/spare bits for a secondary media rig, which is strangely satisfying!

 

[dodonpachi]

I am going to bump this as I have been putting off upgrading but now really need to. I have been using the bungled y adapter and everything seems okay (as in it works), although I am a bit underwhelmed by the 280 performance. I am running things at 1080p and can't get games like Wolfenstein to run smoothly at all. Metro 2033 redux runs okayish at med/ high settings but not at all constant 60 fps and in open environments it gets fairly juddery. Tomb raider claims around 50 fps when bench marked with high settings but in game there is a fair amount of judder when panning around environments. Older things like Dishonored are pretty much 60 fps smooth. I am sure this card should be performing better! Am I just expecting too much from my card? Could my PSU be causing the issue? My card is at 980 Mhz by default and GPU tweak seems to show it behaving normally, overclocking slightly seems okay also (although it is generally quite noisy), I don't get random shut offs etc.

So my questions are:

Could my PSU and imperfect connections (see original post) cause my card to "under perform" or is my 280 just not as capable as I thought?

What PSU (modular or non modular) should I go for right now? The Antec and Seasonic suggested above are both pretty much discontinued everywhere. Is there something more up to date I should be looking at?

Thanks again

 

[Dangman]

I highly highly doubt the PSU is affecting your performance. AFAIK, there's no real GPU tech that downgrades its performance based on the PSU's connections. Here's the thing: I've seen MSI and Gigabyte cards comes with a 6Pin to 8Pin PCI-E adapter where there's only one 6Pin PCI-E connection required. So I'm not sure why the adapter you have requires two 6Pin PCI-E connections.

I do in fact have a R9 280 and its performance has been great for me. No stuttering whatsoever in Tomb Raider. Average FPS in TR is apparently 55FPS on high according the benchmark.

The Seasonic is still available:
http://www.scan.co.uk/products/550w-seasonic-g-series-hybrid-modular-80-plus-gold-1x120mm-atx-psu