Power questions for Visiontek Radeon HD6950 2GB

[willstrotheide]

I just purchased a Visiontek Radeon HD 6950 from TigerDirect. I normally get my parts from Newegg but Tigerdirect charged $30 less as it's refurbished and also, I didn't have to pay taxes or shipping costs. After purchasing, I realized that I lost my spare cables (mainly my pci-e power cable) that came with my Raidmax modular power supply during my last move. Figured I'd have to buy replacement cables for it but have noticed a few things after I have already payed for the card.

I'm upgrading from a Sapphire Radeon HD 5670 which did not require a PCI-E power cable. TigerDirect does not show it but after looking at the pictures of the card on Newegg, it shows with it what looks to be a 6 pin pci-e power adapter that that females what looks like 2, 4pin power cables. I'd assume the adapter comes with the card through TigerDirect as well so I would think that should solve my problem as I have plenty of spare 4pin power cables in my case. But I also noticed that the card has spots to plug in 2 6 pin cables. Can anyone explain what I am gonna need to purchase (if anything) to get this card the power it needs? Links for Newegg and Tigerdirect are below.

TigerDirect (what I purchased): http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1751379&sku=V261-6953

Newegg: http://www.newegg.com/Product/Product.aspx?Item=N82E16814129171

 

[saratj1]

The 6950 requires 2 six pin power connectors, in the newegg pic it comes with a 4 pin molex to 6 pin pci-e adapter. Really you need one pci-e 6pin from your power supply and can use a molex (4 pin) to 6 pin adapter. Using two molex adapters to power the card may damage something.

 

[willstrotheide]

I just bought a 6pin PCI-E extension to replace the one I lost. So technically I can use the extension to power one connector and the molex to 6pin PCI-E converter that comes with the card to power the other connector correct?

 

[alrobichaud]

The max power requirements for that card is 225W under full load. Here is a good article on pci-e power cables.

http://www.tomshardware.com/reviews/power-supply-specifications-atx-reference,3061-12.html

Basically, the standard rated power for a 6 pin pci-e connector is 75W. An 8 pin is 150W. The pci-e slot provides 75W. The max rated power for a molex connector is 187W. This is a quote from the article:

' Even though the specification allows for a delivery capability of 75 W (six-pin connector) or 150 W (eight-pin connector), the total power-handling capacity of these connectors is at least 192 and 288 W, respectively, using standard terminals, and even more using the HCS or Plus HCS terminals.'

So, Yes, you can use the molex to 6 pin converter to power the other connector. I don't see any reason why two molex to 6 pin connectors would not be enough to power that card, though I have never tried it.

 

[willstrotheide]

I should be good to go then. The replacement PCI-E extension cord should power one of the card's slots and the molex to pci converter that comes with the card will power the other slot. So I guess my problem is solved. Though I'm curious. The replacement PCI-E extension cord will arive a few days later than the card so if I decided to throw the card in immediately (purely hypothetical as I don't mind waiting), I could probably power the card off the power from the motherboard and the molex to pci-e converter? It would just crash if the card was on high load I'd assume?

 

[alrobichaud]

If the card does not detect sufficient power connections then the fan will spin at max speed constantly. Most likely it will crash when you try to run a game. The card is still looking for power through both connectors so if one is missing the results may be undesirable. Even though the theoretical absolute max power from either a molex or single pci-e 6 pin connector may be enough to power the card in conjunction with the 75W from the slot, I would not do it. No one really knows how the power distribution is inside the card so trying to send all of the power through one pci-e connector into the card may have some damaging affects. I would be curious to see what would happen but I am not going to risk it with one of my cards and I suggest you not try it either.

 

[saratj1]

If your refering to just a pci-e extension (to make the six pin from your power supply longer so it reaches your card) plus a molex to 6-pin adapter then you'll be fine. I have used those extensions before (NCIX has some sleeved ones that look awesome) and didn't have any issues.

 

[alrobichaud]

If your refering to just a pci-e extension (to make the six pin from your power supply longer so it reaches your card) plus a molex to 6-pin adapter then you'll be fine. I have used those extensions before (NCIX has some sleeved ones that look awesome) and didn't have any issues.

I believe he is waiting on a replacement modular pci-e power cable from the power supply and currently only has on 6pin to molex adapter.