My build formula v mobo has 2xs 4 pin needed on psu

You can use a 4pin connector on an 8pin board. Just plug the 4pin in the slots closest to the CPU. It will work fine.

Also 1000W is very overkill for almost any machine. 650W is more than enough for a single card rig.

ok ty for your response i feel i need to fill you in with a little more information first i will be using these items in my build and upgrading to 2 sli graphic cards R7970 hd black edition but this is not what the 4 pin configuration is for its for the overclocking on the fx 8150 8-core cpu so can you kindly just name some psu's with this 2 of 4 pin connectors @ 1kw ty for any reply

750W is plenty for dual 7970's and an FX-8150.

Theres one.
Silverstone 1KW, 80+ Gold fully modular. $190
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Now that's not bad i must admit thanks for your suggestion my friend appreciated anymore plz post em ty ill look on reviews and pick the most stable-quiet hense a lil power hungry = turn fan down= less noise   and not so much heat

erm a can of worms has been opened now i have just seen the light and was wondering is ErP / EuP not ready a thing to worry on ? in this build.

ErP/EuP is a standard set by the European Union that at complete power off, the system will consume less than 1W. You need a ErP/EuP ready motherboard as well.

Its not that important, your machine will run just fine without it. And the power draw of a non ErP/EuP system when powered off will still be tiny.

ere whats wrong with this picture
http://www.scan.co.uk/products/1200w-silverstone-stride...
i can get for £139.99
and
http://www.scan.co.uk/products/1000w-silverstone-tech-s...
i can get for £169.98
what am i missing here >seems wrong lol

200w is what you are missing.

yer but for £30 less i gain 200 watts

Thats not what I'm seeing.

1200W - 154 Pounds
1000W - 139 Pounds

Silverstone Strider 1200W Modular '80 Plus Gold' Power Supply (SST-ST1200-G)
The Strider Gold models are built on similar platform as the award-winning Strider Plus series but with even higher efficiency ratings.
Average rating of 5.0 Silverstone 10+ in stock £139.99

Silverstone Strider Gold 1000w '80 Plus Gold' Modular Power Supply (ST1000-G)
To make great power supplies even better, SilverStone engineers delved into the details with the Strider Gold series.
Silverstone 3 in stock £169.98

a lttlel update for anyone interested i put the Silverstone Strider 1200W in my basket and when i re-logged in after depositing money in bank for that and OS saw that price had rose to £199 but luckily i had it in my basket and still got my delivery at £139.99 thank you overclockers  

my new thred is ...XFX Radeon HD 7970 FX-797A-TNBC compatible with other in its range for CF?

SLI is with Nvidia cards, Crossfire is AMD.

It has two crossfire connectors (meaning it can get up to 4 cards in Crossfire), and there isn't any reason why it wouldn't work.
You can mix brands in a Crossfire setup, though you are better having identical cards.

XFX Radeon HD 7970 Black edtion has a overclocking option on it what would this mean if used in CF would i need to OC the same card to same speeds ect for them to work in tandem or is OC only ment for single card use?

You can clock the cards to different speeds in a Crossfire setup, but can lead to issues. Best off clocking them the same.

can you crossfire HIS Radeon HD 7970 X2 with r7970 black edition? this is exciting news on the gfx front i hope there compatable but not alot out there to say wether i can or not ?