Need new/ more memory

You need to provide a bit more detail. If you get better/more memory, but your video card is terrible, it won't do you any good, because the limiting factor is not the ram. if on the other hand, you have great components elsewhere in your system and the ram is what is holding you back, then you will certainly see an improvement in performance by increasing the quality and/or quantity of your ram.

"by how much" is going to vary widely depending on not only the above, but also a number of other factors (what program/game you're running, what else is on in the background, etc).

lastly, to be honest, and with all due respect, if you are unsure if going from 4 gb of ram to 8 gb of ram will help your system, you probably are not at the experience level that you should be overclocking components, and run the risk of damaging your hardware while very likely experiencing minimal if any improvement in performance.

i know that overclocking sounds cool, but like putting nitrous in your car, it's probably best left to those that better know what they're doing, it's dangerous and unless your machine is already top notch in every other way, it won't gain you nearly enough to validate the risk.

So if the question is can you benefit from 2x4GB Corsair Vengeance? The the answer is yes for Gaming, Rendering and Huge Databases, but regular Apps you'll get zip unless you run out of RAM and are excessively hitting the virtual memory. Obviously you'll need a 64-bit OS {don't use XP 64-bit}.

Nice Article -> http://www.tomshardware.com/reviews/ram-memory-upgrade,...

As far as OC the RAM then that's a hit and miss even with Corsair, as long as you run Memtest 4-passes without errors then use the OC   On Sandy Bridge and gaming the differences between Rated 1600 and OC 1800 won't do a thing -> http://www.bit-tech.net/hardware/memory/2011/01/11/the-... Multi-tasking a marginal improvement; it depends on the activity.

sorry for lack of detail was in a rush i have a good graphics card got the asus 6970 direct cu 2 1090t x6 750watt psu standard 7200rpm hdd all air cooled cant remember the motherboard but need to get another one soon. so will it increase performance by much?

The 6-core AMD can run up to 2000 MHz RAM, so the question is about benefits in those circumstances. Fast RAM helps but only maybe 2~4FPS typically, and in order to run 1800+ RAM you need to OC the FSB or don't bother and get 1600s.

Next is amounts, even a discrete GPU uses 'shared' RAM or about 3GB and if you run CF {or SLI} then more. This 'shared' RAM all depends upon your 'Free' RAM, but keeping the 'shared' to it's maximum only aides GPU performance; hence the 'Nice Article' above. RAM is so cheap that I only recommend 4GB/stick density.

Here's an example from my wife's PC, you can compare yours to see what I'm talking about -> http://i1013.photobucket.com/albums/af254/Jaquith/WEI_H...

OK well ill probably be sticking with the 1600 and seeings i can get vengeance 8gb for 60/£70 from Amazon which is pretty much what i paid for and overclocking wise ill put it too what i have it at the moment and also because i haven't got a reply from my other post i need a new motherboard preferably with sata 3 mainly because im planing to put my old parts on the motherboard im using at the present any ideas on good one? i dont want to pay mega money like some people do because it seems a waste to be honest.

MOBO: Define 'old parts' what are you reusing? I assume since you're didn't seem interested in increasing the FSB that you're not interested in OC?! However, the AMD 1090T is all about OC?! Since you are running ATI/AMD GPUs then look at 890FX or the 990FX {very expensive} chipsets.

Q - How many GPUs will you be running?
Q - What's your Budget?

Examples of 890FX:
MSI 890FXA-GD70 http://www.newegg.com/Product/Product.aspx?Item=N82E168...
ASUS M4A89TD PRO/USB3 http://www.newegg.com/Product/Product.aspx?Item=N82E168...
OC ASUS Crosshair IV Formula http://www.newegg.com/Product/Product.aspx?Item=N82E168...

990FX:
Gigabyte GA-990FXA-UD5 http://www.newegg.com/Product/Product.aspx?Item=N82E168...

1 gpu maybe 2 for the future but at the moment just want a few ideas haven't got a budget but just don't want to spend a fortune and i am interested in oc still learning and they all seem a reasonable price any more ideas?

HD 6970 CF, AMD 1090T, 1600 MHZ RAM and Gaming then ASUS Crosshair IV Formula 890FX or Gigabyte GA-990FXA-UD5.

Also, you might want to look into 1800 MHz RAM if you're also going to FSB + CPU Multiplier OC the math works out better in most instances.

will look into it now while i have the chance to and thanks for the advice much appreciated