Help me choose my computer components.

[Guest]

I've selected all the parts i think i'll need but i'm getting stuck when it comes to the power suply. i'm not sure if a) the power suply i have selected will suport the amount of power i'll need and b) if the graphics card is suported by the PSU.

For my system i'll be using:

650W Corsair CMPSU-650TX, single 12V rail
6GB (3x2GB) Corsair XMS3, DDR3 PC3-12800 (1600)
LG CH08LS10.AUAU 8x Blu-Ray Reader
Coolermaster HAF 922, Black, Mid Tower Case
MSI P55-GD65, Intel P55 Express
Intel Core i5 750, Lynnfield 45nm, Quad Core, 2.66GHz
800GB Western Digital WD8000AARS
1GB DDR5 Asus HD 5870,

Now the confusing part. When i buy my computer i'll only be buying one graphics card right away (i'll want to order the second one after a month or so) I'm just unsure if my systems PSU would be able to cope with that amount of power needed. If it can't i'll just have to find another PSU. Thing is alot of people are saying i'll need atleast 900w power. But then my Uncle thinks that the 650w should be enough as it is a high quality one and will give out more power than a cheaper one with a higher rating.

What do you guys think?

 

[Lmeow]

Ok, all looks good except the RAM. That Corsair 6GB kit is triple channel, and is designed for LGA 1366 Core i7 900s on the X58 chipset. You need either a 4GB or 8GB dual channel kit. For example, here's the G.Skill Ripjaws 4GB DDR3 1600MHz dual channel kit for $119.99:

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231278&cm_re=g.skill_ripjaws-_-20-231-278-_-Product

As for the power supply, I suggest you get a Corsair HX750W or TX750W, two HD 5870s in CFX full load with a Core i7 o/c to 3.5GHz take around 600W, which is around 90% load and will probably put a bit too much stress on the PSU, I'd say an i5 system would be taking 550W, but you do not want to max out your PSU - it's more efficient between 20% and 90% load, where 50% is optimal, thus getting a 750W PSU would be more efficient and safer.

 

[Guest]

Oh right cool, thanks i never noticed about the RAM. i would have bought that to find out it wouldnt have even worked. Ok so it looks like i'll need to go for a more powerfull PSU. I think the money i save from downgrading the ram can go towards a better PSU. Do you think 4GB DDR3 Ram will be sufficent to run games on high settings?

 

[Lmeow]

Well, the 6GB kit would work, but it would be running it in single channel, which may have some performance impacts. As for whether 4GB is enough to play games on high settings - I'd say more than enough, it's far more based on the graphic card and CPU.

 

[Guest]

So my system should be ok then? I just worked out the price - going for 4GB DDR3 ram Dual channel and a Corsair 750tx PSU works out cheaper than i was going for in the first place!

So just to clear things up, running 2 ATI 5870's in CFx on a system using a 750w PSU should be fine? anything else i should look into?

 

[janxta]

The PSU that you chose, 650 watts is more than enough for your system even if you overclock both the cpu and gpu. Corsair makes excellent power supplies and you will be using yours for years to come. Enjoy getting your build up and running.

 

[Guest]

The PSU that you chose, 650 watts is more than enough for your system even if you overclock both the cpu and gpu. Corsair makes excellent power supplies and you will be using yours for years to come. Enjoy getting your build up and running.

But can it run 2 GPU's? Thats what i'm confused about. I found a 750w one incase it cant but i'd obviously prefer to spend less lol

 

[Lmeow]

The PSU is more than enough, but it'll be running at near max capacity and full stress when the GPUs are on max load, thus it'd be much better to get the TX750W, and I'm supposing you're going to be overclocking too. If you don't mind risking it, get the HX650W - the TX650W only has two PCI-e connectors, and it's best not to use any adapters.

http://www.legitreviews.com/article/1105/14/

600W full load - 90% load on PSU, the fan will probably be very loud, and long term stress will probably be bad for the PSU. The system they are using is more power hungry though, with an i7 975 at 3.33GHz.

 

[Guest]

I'm not entirely sure if i want to overclock it. it's not the slowest processer, would OCing it be of much benifit?

It is only a 2.66Ghz afterall

 

[Lmeow]

Well, with Core i5s, overclocking can give quite a large increase in performance depending on the application. You will need an aftermarket cooler if you want to push it further than 3.2GHz or so. Something like the Cooler Master Hyper 212 Plus for $34.99, which is a very good price/perf cooler.

 

[Guest]

Oh right, I think i'll leave that bit for now. If i find that i want it to go faster though atleast i know i allways have that as an option.

 

[randomkid]

Here is a power supply calculator that will give you good estimate of how much capacity your PSU should have given your components. It even gives consideration if you are overclocking or not.
http://extreme.outervision.com/psucalculatorlite.jsp
I see that you have selected an i5 750 and an HD5870. I come to my favorite question: What is your monitor size and its resolution?