I'm buying a MSI 7970 Lightning this friday and need help.

OptimaLnrg · 9 Oct 2012 at 17:41

680 MAX power draw (furmark?) = 228w

add some for the lightning..

slot = 75
2 x 6 pin = 150
=225w

slot = 75
1x 6 = 75
1x = 150
= 300

So split the true 8 pins, 1 for each card and should be fine, no?

Rusty0611 · 9 Oct 2012 at 17:44

gregster said:
But you miss my point about the 2 8 pin connectors have 2 of the pins spur off from the 6 pin connectors. Surely this is in reality only a 6 pin connector still?

Nope - that's a 6+2 pin connector. It means it can be a 6 pin or 8 pin depending where it's being plugged in to as a hard 8 pin connector won't fit on a 6 pin socket. It also means PSUs are flexible with their PCI-E power leads and can cover all kinds of set-ups.

I have 4 of them

.

If I were you I'd split one 8 pin on each and then a 6 pin into each.

thenewoc said:
It's not scare mongering! The 680 Lightning has two 8 pin connectors on each and therefore there must be a reason for it having those otherwise they'd put 6pin ones on it. Gregster stated he only has 2 6+2pin connections and 2 6pin connectors. Personally I'd want to connect 2 6+2pin or 2 8pin connections to each card as that is what the design suggests is required. It is also no bad thing to have more than enough Watts rather than running things closer to their max.

It is.

Considering a reference 680 runs of 2 * 6 pins quite easily and you can't voltage adjust these ones.... factor in the MSI Lightning overvolting slightly... 2 * 8 pins? No way. It's a marketing gimmick to make you think it's taking in loads of power and therefore is massively more powerful. It's worked on you!

The Gigabyte Windforce 3x has a 8 pin and 6 pin socket on it and it's essentially a custom cooled reference card so if you don't believe it's clever marketing then you'd be being short sighted.

thenewoc · 9 Oct 2012 at 17:45

^ I said:

Depends what wattage your PSU is delivering down those PCI-E 8pin and 6pin connections, it may be more prudent to put one 8pin connection on each card rather than having both going to the same card.

Gregster · 9 Oct 2012 at 17:53

Rusty0611 said:
Nope - that's a 6+2 pin connector. It means it can be a 6 pin or 8 pin depending where it's being plugged in to as a hard 8 pin connector won't fit on a 6 pin socket. It also means PSUs are flexible with their PCI-E power leads and can cover all kinds of set-ups.

I have 4 of them .

Fair comment. I know very little on PSUs but I will not be shelling out more money unless Antec advise that it is not man enough. Also, the 2 6 pin connectors plug into 2 8 pin sockets on the PSU...

I guess this means that any 6 pin to 8 pin extension cable I use will then effectively be a true 8 pin connector?

Rusty0611 · 9 Oct 2012 at 17:58

gregster said:
Fair comment. I know very little on PSUs but I will not be shelling out more money unless Antec advise that it is not man enough. Also, the 2 6 pin connectors plug into 2 8 pin sockets on the PSU... I guess this means that any 6 pin to 8 pin extension cable I use will then effectively be a true 8 pin connector?

The sockets on the PSU are generic irrespective of 6/8 pin.

On the card 6 fits into 8. But 8 doesn't fit into 6.

6+2 fits all

Honestly mate - while your connections might not be matched up exactly to the physical dimensions of the sockets on the card they are providing enough power to your card and I doubt you'll be running anywhere close to what you would call the limit of your PSU.

As I said 450W for me with the occasional spike to 500W. Add on a fair bit for SB-E and a wee bit for the Lightnings... I wouldn't like to guess but you'll be close ish with a fair amount of wiggle room still.

Gregster · 9 Oct 2012 at 18:07

Ok ta. As I said, I will not be buying another PSU purely on guess work from some of the posters here. I am at work till 10 but will be emailing Antec for verification either way.

spoffle · 9 Oct 2012 at 18:10

Rusty0611 said:
On the card 6 fits into 8. But 8 doesn't fit into 6.

8 pins fit in to 6 pin sockets. I've got an 8 and 6 pin connected to my 6950 right now.

Gregster · 9 Oct 2012 at 18:16

I will buy one of those power monitors that Tommy linked to a few threads ago. I am curious how much power I use anyways. I imagine the 3930K @ 1.495V draws a fair bit of power.

Uncle Petey · 9 Oct 2012 at 18:17

Fwiw, my card requires 6+8pin.
My PSU PCI-E 6+2 cables both have 7 cables wired.

It's all jiggy.

Rusty0611 · 9 Oct 2012 at 18:53

spoffle said:
8 pins fit in to 6 pin sockets. I've got an 8 and 6 pin connected to my 6950 right now.

Does it? Fair enough.

Must have got my wires crossed...

... no pun intended

spoffle · 9 Oct 2012 at 18:55

It might depend on the card you've got, on my 6950 there's a gap between the two 6 pins, but an 8pin cable, the first 6 pins from left to right are exactly the same as the ones on a 6 pin.

If there's enough space around the socket, an 8pin will fit in a 6 pin one, but if you've got a card where the two 6 pin sockets are right next to each other with no space either side, it won't fit.

RetrogamerX · 9 Oct 2012 at 18:59

gregster said:
As I said, I will not be buying another PSU purely on guess work from some of the posters here

When a lot of users say your psu is crap I take it it's crap. I didn't know what psu I was getting when I ordered this PC. I thought I was getting a pure gaming machine and that meant everything in the PC would be game worthy. I was wrong. So Cammy helping me out on the right PSU was the right thing to do. I need a good PSU that will last a good year or 2. PSU's are cheap, so If I do need more power in the future I'll just buy another.

As quoted from you gregster...

Simples

One question. My gpu now is a XFX 7850 Core, when I get my new msi tfiii 7950 will the same drivers work for this new card?

cammy5477 · 9 Oct 2012 at 19:20

gregster said:
I will buy one of those power monitors that Tommy linked to a few threads ago. I am curious how much power I use anyways. I imagine the 3930K @ 1.495V draws a fair bit of power.

Here I go scaremongering again gregster :-)

but isn't V absolute 1.4v on SB-E? Intel specs not mine
Just saying mate you seem like a decent guy unlike that other gimp. Don't think your chip will stop working but it will degrade fast making it hard to overclock. I won't take mine over 1.4v even under a chiller.

Tonester0011 · 9 Oct 2012 at 19:30

cammy5477 said:
Here I go scaremongering again gregster but isn't V absolute 1.4v on SB-E? Intel specs not mine
Just saying mate you seem like a decent guy unlike that other gimp. Don't think your chip will stop working but it will degrade fast making it hard to overclock. I won't take mine over 1.4v even under a chiller.

They're just advisory...it's down to your cooling and your chip.
Degradation isn't just about the voltage, the heat is a big cause.

Chances are you'd upgrade well before any noticeable degradation occurs...

@Greg, when you get your power meter, i'd be surprised if you're using 600w...
My rig has peaked at 700w from the wall, that's with 2 7970s @1278mv, 8Sythe GT, 3770k @1.35v, D5 + others. Normal gaming i use about 500-550w.

psychodil · 9 Oct 2012 at 19:31

cammy5477 said:
Just saying mate you seem like a decent guy unlike that other gimp. .

No need to talk like this on a forum, even if you disagree with someone. Save it for the playground.

Gregster · 9 Oct 2012 at 19:47

It's all good and I can think for myself

I will ask Antec and probably ask MSI also. Just an open discussion fellas and be nice even if you disagree

andybird123 · 9 Oct 2012 at 19:54

the psu failing is not an issue (unless it can't supply the amps the card needs over the rail it's own) the problem with 6-pin vs. 8-pin is that a card drawing too much power through a 6-pin will overheat the connector and cause voltage drop which will cause instability

i don't think anybody's psu is in danger of failing entirely

andybird123 · 10 Oct 2012 at 10:05

don't know how I missed this one... a 6-pin connector (according to the spec) should have 2 12v+ and 2 ground wires with 1 signal
an 8-pin connector has 3 +12V, 2 ground and 2 signal

take a look again at your 6-pins... they have 3 +12v and 2 grounds, the only thing it's missing is a second signal wire to tell the card it's an 8-pin... so the straight 6-pin to 8-pin connector will be fine as it then has the right amount of +12V and ground wires for an 8-pin, and gregster is also fine using 6-pins in to his 8-pin cards

Gregster · 10 Oct 2012 at 10:32

^^ Good to know cheers Andy

I have emailed Antec and MSI for treble confirmation.

Gregster · 10 Oct 2012 at 12:05

cammy5477 said:
Here I go scaremongering again gregster but isn't V absolute 1.4v on SB-E? Intel specs not mine
Just saying mate you seem like a decent guy unlike that other gimp. Don't think your chip will stop working but it will degrade fast making it hard to overclock. I won't take mine over 1.4v even under a chiller.

lol bud. I have had it on 1.495V @ 5GHZ for bench testing (probably about three hours in total). I know all about voltages and acceptable voltages for each chip. Mine is all under water and 24/7 I run at 4.625 @ 1.32V. I appreciate that pointing that out to someone who doesn't know or understand what they are doing is a good thing though

. Intel will specify 1.4V simply to cover them selves.

I meant to reply to this yesterday when I got home from work but forgot.