ASUS HD6970 DirectCU II with XFX Core 550W PSU?

[NTxC]

Hello,
I decided to build a gaming PC, so I recently bought an ASUS Radeon HD6970 2GB DirectCU II. When I asked for an optimal PSU choice I have been recommended an XFX Core 550W. So, I bought it, only to find out that it only has one 6pin PCI-E plug and one 6+2pin PCI-E. But the Radeon requires two PCI-E 8pin power connectors. There is a red LED glowing on the back of the VGA's PCB... It appears to me I've wasted money on this PSU, because it doesn't even have the needed connectors...

Rig:
CPU: Intel Core i5-2500K @ 3.3GHz
VGA: ASUS Radeon HD6970 2GB DirectCU II
PSU: XFX Core 550W
RAM: A-DATA 8GB 1333 Gaming Series CL9
M/B: ASRock Extreme3 Gen3 Z68

Could you please give me some advice?
Is this PSU even enough to handle the rig?
I also saw a 2xMOLEX -> 8pin PCI-E adapter, would it be any good for me? The PSU has plenty of MOLEX connectors.

 

[purple stain]

Actually that PSU is a really good quality unit and it has all of the connectors you need your just not looking close enough.

The 6970 actually only requires an 8pin and a 6pin.You should be using the 6+2pin and the 6pin PCI-E connectors to power the 6970.

That PSU is plenty to power your rig but if you plan on Crossfiring anytime soon I would suggest upgrading your PSU.

 

[NTxC]

Thanks for the reply.
I did this now:
I connected the PSU's 6+2pin into the first 8pin socket.
The 6970 came with a 2x 6pin PCI-E -> 8pin PCI-E adapter, so I used it for the second socket, but I connected only one of the 6pin plugs, and it seems to work. But doesn't that limit my OC capabilities?

 

[N.Broekhuijsen]

Yeah the 6970 DirectCUII from ASUS has 2 8 pin connectors. Very sexy.

Just have a look that the PSU can deliver enough current for the GPU, although I'm not so worried. Make sure you have the connections spread out accross the different 12V rails, ie; connect some through PCIe connectors, other leftovers via molex adapter you suggested

 

[purple stain]

Oh i'm sorry.Didn't see that.I just assumed all 6970's only required a 8pin and 6pin.

You shouldn't use the card at all if you don't have the proper power connections.You risk damaing the card.It should have came with a molex adapter.If it didn't you'll need to get one.

As an alternative you can use the 8pin CPU power connection for the GPU and use the 6 pin for the CPU.This will work but don't O.C. the CPU to much.

 

[N.Broekhuijsen]

Well I'm using one PCIe 8pin connector, and the adapter that came with it that has 2 six pin to 8 pin, connected to that I have one of the six pin PCIe connectors, and using an adapter from dual molex to 6 pin. It's working fine here, no problems.

 

[N.Broekhuijsen]

in case the explanation didn't make so much sence... not as if this makes any more though... :lol:

 

[NTxC]

Oh i'm sorry.Didn't see that.I just assumed all 6970's only required a 8pin and 6pin.

You shouldn't use the card at all if you don't have the proper power connections.You risk damaing the card.It should have came with a molex adapter.If it didn't you'll need to get one.

As an alternative you can use the 8pin CPU power connection for the GPU and use the 6 pin for the CPU.This will work but don't O.C. the CPU to much.

The CPU 8-pin has a different layout to the PCI-E 8pin connector, so it wouldn't match. Right now I bought a Dual Molex -> 8pin PCI-E adapter, going to test it soon. I'll post the results.

 

[GreenDutchAlien]

"As an alternative you can use the 8pin CPU power connection for the GPU and use the 6 pin for the CPU.This will work but don't O.C. the CPU to much."

I think that can even be dangerous ( if it would fit anyway )

 

[N.Broekhuijsen]

hey look a fellow dutchman!

of ben je niet nederlands?

 

[GreenDutchAlien]

God, not another one ! :lol: yes i am zeker wel Nederlands to.

 

[purple stain]

"As an alternative you can use the 8pin CPU power connection for the GPU and use the 6 pin for the CPU.This will work but don't O.C. the CPU to much."

I think that can even be dangerous ( if it would fit anyway )

How?

 

[GreenDutchAlien]

I did read a thread about pcie pins and a mod stated that. I'll try to find it for you. Could take a while though.

 

[GreenDutchAlien]

Ha, that was fast ; http://www.tomshardware.co.uk/forum/forum2.php?config=tomshardwareuk.inc&cat=15&post=333045&page=1&p=1&sondage=0&owntopic=1&trash=0&trash_post=0&print=0&numreponse=0&quote_only=0&new=0&nojs=0


Moderator JSC stated ; Graphics cards use either 6 or 8 pin plugs for power. Do not use a 4 or 8 pin CPU power plug. They are wired differently. Using the wrong one will result in shorting 12 volts directly to ground.

 

[purple stain]

Oh I see.I didn't think it was that much of difference since they both use the +12/v rail.

 

[purple stain]

I saw in that thread you were saying you'd rather an XFX PSU.Just wanted to let you know that most of the XFX PSU's are made by Seasonic so it's basicly the same thing either way.

 

[GreenDutchAlien]

Ha, lol, good info that. Didn't know. They look cooler anyway And often they are a bit cheaper. Thought the seasonic was 10 or 20 bucks more for basicly the same psu.

 

[purple stain]

I'm not sure how the marketing goes I just know that most of the XFX PSU's are made by Seasonic which is why they are such good quality.

 

[NTxC]

Got the 2xMolex -> 8pin PCI-E adapter, and now the system works flawlessly.
Temperatures are good I guess, GPU: 29 C idle, 50 C at load; CPU: 23 C idle, 40 C at load. No OC yet, of course. Definitely need to try it soon.

 

[erelyes]

In terms of whether you actually need to use both 8pin PCI-e power sockets on the graphics card; read the manual. My MSI HD5870 Lightning has two 8pin connectors, but the manual says only an 8+6 is actually required.

6pin connectors support 75W, 8pin support 150W. This is in addition to what it draws from the slot.

Good to hear it works though. I would suggest you're probably near the limit of what the PSU can handle though.