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Elegy
07-13-07, 04:31 AM
I'm hoping to get a system with a Q6600, 3GB memory, 500GB hard drive and 8800gtx. I don't plan to do any overclocking or upgrading to this system but I would like it to last a minimum of 3-4 years.

Will this PSU be enough to power this system? CoolerMaster eXtreme Power 600W (http://www.coolermaster.com/products/product.php?act=detail&tbcate=22&id=52)

SLippe
07-13-07, 05:29 AM
Yeah, that one should be fine, unless you ever plan on goin' SLI, then maybe not.

Elegy
07-13-07, 06:20 AM
Thank you. Does anyone else have an opinion about how suitable this power supply is? The more opinions, the fairer my final decision will be.

I read in another thread sometime ago though where I believe Xion (apologies if it wasn't you, I can't quite recall) said that one should avoid dual rail PSUs and instead go for single, tri or quad rail ones? The PSU I'm considering is dual rail. I can't remember why exactly, I'll try and find the thread...

EDIT: It was Xion. He said:

One of the mistakes I see people making time and time again is thinking you can calculate the leftover amperage/wattage on the first 12v rail into the picture for the rest of your components. You can't. On 95+% of the PSUs out there, 12v1 is dedicated to the CPU and CPU ONLY. Any excess wattage or amperage cannot be used to power other components with. This is done as a safeguard for the system so that it insures it's always running at the most basic level. If the CPU loses power, the entire system dies.

You don't have that problem with single-rail PSUs.

This is why many PSUs that the original poster suggests--those that fall in the 400W==>600W range--aren't recommended. They are normally dual-12v rail models and are horribly, horribly optimized for high-end systems. Owners of dual-rail PSUs often believe they have twice the amount of amps/wattage to run their components off of than they actually have. I have personally witnessed 3 different dual-rail models--all 550W or greater and name-brands--fail under load from a system that was sucking no more than 350W-400W from the wall. I have spoken with countless others across the web who had the same issue.

The best route to take is to either go with a strong single-rail PSU in the 450-600W range, which there aren't many of (the Silverstone ST56ZF Zeus is a great one), or to go with a high-end tri or quad-rail model that has an abundance of amps on two or more 12v rails. Dual-rail PSUs just fail under the load of high-end systems because most of the time the excessive amperage/wattage on 12v1 cannot be used.

And like has been mentioned, also, many of the PSUs with the least ripple and best voltage stability are high-end models. When you're running 500$ graphics cards in your system, you want to supply it with clean power. And any Average Joe with any scintilla of knowledge about PSUs knows that the stronger the load the PSU is under, the higher the ripple usually gets. Therefore, if you're running a 450-500W PSU near maximum capacity, you're approaching the highest ripple area which, in some cases, exceeds ATX specs and can cause damage to your components.

Until most of these PSU companies get their act together and stop making dual-rail PSUs/ start building higher quality models with less ripple on the high-end, this will remain a problem. Dual rails are starting to become a little less common with the emergence of more single-rail models.. even on the high-end (the Silverstone Olympia 1000W, for example.)

On top of all of this (yes, there is more), we haven't even covered the subject of pushing a PSU near its maximum capacity causing a high failure rate. Most of them aren't made to do that. I've seen several on this forum who've tried and had their systems fail on them within weeks from attempting this. And these were with name brands like OCZ, PCPower & Cooling, etc.

Technoholic
07-13-07, 01:56 PM
600W is good.

I have Corsair 520W... 4 HD's (all in sig), 2gig of RAM, E6400 @ 3GHz, 8800GTX.....ya know, the rest is in my sig.

Elegy
07-13-07, 03:43 PM
600W is good.

I have Corsair 520W... 4 HD's (all in sig), 2gig of RAM, E6400 @ 3GHz, 8800GTX.....ya know, the rest is in my sig.

The only difference is, your power supply is tri-rail and can supply up to 480W on the 12V rails. The 600W I'm considering is only dual rail and supplies only 432W on the 12V rails. I guess I'll have to ask the company I'm buying from if I can upgrade to a better PSU or do it myself without voiding the warranty *sigh*.

Thank you for the feedback though.

Elegy
07-14-07, 01:20 PM
Does anyone happen to know whether one of the 12V rails on the "CoolerMaster eXtreme Power 600W" supplies power to only the processor? I've been emailing them about it and they haven't replied.

If both rails can supply power to any of the components, it should be more than enough for my system. Assuming of course that the 600W and 2x18A figure is actually accurate, which is a pretty big assumption. If one of the rails only supplies to the CPU, it will definitely not be able to power the system - 18A to the graphics card and the other components is nowhere near enough.

Buckeye
07-14-07, 04:42 PM
Not sure what to think of that Quote posted above, sounds like marketing hype to me and something I really wouldn't worry about to much.

I ran a Enermax 535W before on my older system with 2 BFG 7600 OC's in SLI plus 4 HD's, 2 Burners and all that jazz, not one problem. Upgraded that same system with 1 BFG 8800 GTX and it ran perfect. That was a AMD 4200+ Dual Core, 2 gig ram etc etc.

Stick with name brands that say SLI cert even if not building a SLI machine and you should be good to go. Go to a trusted site like Guru3D and read some reviews there and then pick from what they say is good.

Elegy
07-14-07, 04:49 PM
I've been looking around and a lot of people seem to be saying that this Coolermaster can't handle high end systems. I'm surprised one of the most reliable companies in the UK (Evesham) ship Q6600, 8800gtx systems with this supply.

I can't ask them how the warranty will be affected by changing to another power supply yet since it's the weekend, but would this power supply be strong enough to handle my system, bearing in mind I'll be using it intensively and want it to last an absolute minimum of three years?

OCZ StealthXStream 600W (http://www.ebuyer.com/UK/product/127861)

It has the same wattage but has quad rails, can deliver a greater current over the 12V rails, is a named brand and I've seen no negative things being said about it.

I just wish Coolermaster would be more open with the exact specifications of their supplies.

nicepun
07-14-07, 09:30 PM
I still don't understand why people go and buy a very expensive GPU and a QuadCore CPU and then try to skimp on the PSU which is the thing that holds everything together. If you can afford to spend $500+ on a video card, then you should be able to spend a reasonable amount on a solid PSU.

Example (http://www.hardforum.com/showthread.php?t=1207398)

Now don't be a tightwad a get a good PSU. Single +12V Rail is what you want to get, specially when dealing with a quadcore.

Elegy
07-14-07, 09:49 PM
I still don't understand why people go and buy a very expensive GPU and a QuadCore CPU and then try to skimp on the PSU which is the thing that holds everything together. If you can afford to spend $500+ on a video card, then you should be able to spend a reasonable amount on a solid PSU.

Example (http://www.hardforum.com/showthread.php?t=1207398)

Now don't be a tightwad a get a good PSU. Single +12V Rail is what you want to get, specially when dealing with a quadcore.

I have 1600 maximum in total to spend on a desktop for university, bought from a reseller because I need the 3 years onsite warranty should anything go wrong. I'd really like a Q6600 and 8800gtx. The reseller I'm looking at, Evesham, is really the only one my parents would allow me to buy from because they won the 2006 reliability and service awards. Unfortunately for me, they are also one of the more expensive places to buy computers from and they use the Coolermaster (first post) to power their Q6600, 8800gtx systems, which I'm doubting will power the system given the intensity and duration I wish to use it for.

Buying a good power supply will simply push me over my budget. I originally started with a 800 budget, then basically pushed my parents up to 1600. There's no way they'll go higher.

I've been talking with one of Evesham's sale reps and he says he might be able to offer me a discount if 'the margin of my order is above 21%' but I don't really know what that means. I'm also hoping that the ~120 price drop on the Q6600 on July 22nd will come into effect on their desktops by mid-August. Unfortunately, I can't take either of these things for granted and I have to assume I'll be receiving no discount and that the CPU savings won't come into effect in time.

I'm planning to talk with the sales rep on Monday again and pointing out how other resellers are ~200 cheaper on some systems and make out that I'm really swayed by them and hopefully they'll lower the price a bit for me. I'm also planning to ask them to upgrade the power supply for me, though I'm expecting nothing at all.

Furthermore, it's not as easy as just buying a good PSU and sticking it into my case. I have no idea how this will affect the warranty.

Buckeye
07-14-07, 10:03 PM
If they sell it that way then you have np with a warranty.

Elegy
07-14-07, 11:04 PM
If they sell it that way then you have np with a warranty.

I know, but the systems they sell come with the coolermaster eXtreme Power 600W, which is only dual rail and looks like a pretty weak supply in general. I'll have to somehow get a better one without breaking warranty.

nicepun
07-14-07, 11:35 PM
Well, given that you'll be throwing alot of money your way you should try to demand a better PSU without any additional cost. Once you show money on their faces it's really easy to do. Trust me, they want to sell things more than you want to buy them. Worst case scenario and if all fails (i.e. they don't give you a free PSU upgrade) you should ask them if it's O.K. if you upgrade the PSU because you don't feel comfortable with the one they include with the system. Just my 0.02 (I'm not sure how much that is in GPs..LOL).

Elegy
07-15-07, 12:00 AM
Well, given that you'll be throwing alot of money your way you should try to demand a better PSU without any additional cost. Once you show money on their faces it's really easy to do. Trust me, they want to sell things more than you want to buy them. Worst case scenario and if all fails (i.e. they don't give you a free PSU upgrade) you should ask them if it's O.K. if you upgrade the PSU because you don't feel comfortable with the one they include with the system. Just my 0.02 (I'm not sure how much that is in GPs..LOL).

Don't worry, I plan to use every tool in my disposal, including the "I'm the customer and I'm spending a lot of money here! Give me better PSUs or I'll buy from somewhere else!", although maybe slightly better worded and more polite :D .

0.02c? That's worth about 0.01p given how strong the pound is against the dollar nowadays.

Elegy
07-15-07, 03:10 AM
I've been doing some research and I came across this:

ThermalTake Power Express 250W (http://www.microdirect.co.uk/(15895)ThermalTake-250W-Power-Express-VGA-Power.aspx)

It's basically a 250W PSU that sits in one of the 5.25" bays and supplies power solely to the GPU. Would one of these be enough to power a single 8800gtx for 3+ years? I'm sure the Coolermaster 600W that comes with the system would be more than enough to cope with my Q6600, 3GB memory, 500GB drive etc... and the 250W can hopefully just provide power to the GPU.

Is it possible for a graphics card to be powered by two seperate units? If the 250W for some reason can't handle the strain, would the 600W main supply divert some power to help out the GPU?

I apologize for all the double posting by the way. I don't have much time left before I have to buy a computer and I need as much feedback as I can get as soon as possible.

BrianG
07-15-07, 08:57 AM
Don't bother with the drive bay PSU. Useless noise and heat.

All that really matters is the amount Amperage available in the 12V rails. Get something that can comfortable support your system and go with it. You do not need a bajilion watt PSU, just a good PSU.

I have a Neo-HE 550 driving my system. My voltages after upgrading from a 7900GTX to 8800GTX did not change. It's quiet, been stable and is modular. Another great PSU/money is the Corsair in 520 or 600 watt flavors. Efficiency plays a role, make sure it is 80+ certified.

I love how Silent PC review does their PSU reviews. Check it out.
http://www.silentpcreview.com/section10.html

Elegy
07-15-07, 10:18 AM
From the link you just gave me:

DUAL 12V LINES: REALITIES

Note that 12V2 is supposed to supply only the AUX12V (2x12V) 4-pin plug, which feeds only the CPU. With PSUs that adhere strictly to the ATX 12V v2.xx Guide, 12V1 then must supply 12V to all the other components that require it.

I suppose that settles it then. 18A isn't enough to supply an 8800gtx and other components without overloading: Source (current on the 12V rails is 19.11A on the "High end" system) (http://www.behardware.com/articles/670-4/pc-s-actual-power-consumption.html)

I'm looking at the Corsair 620W model at the moment and it looks like my dream PSU. Very efficient, very powerful but it costs ~100. This wouldn't necessarily put me over my budget but it means my monitor has to be cheaper to compensate.

I'm considering getting the OCZ GameXStream 700W (http://www.dabs.com/productview.aspx?Quicklinx=4L08&CategorySelectedId=11259&PageMode=1&NavigationKey=11259,50121) which costs only 75. Does anyone have any thoughts on this PSU?

Ideally though, I'd really like to get the drive bay PSU. It's cheap (~25), reviews say it's pretty stable and efficient, it's easier to set up and will affect my warranty less seeing as it only provides power to the GPU. Is there a reason besides the noise and heat why I shouldn't get it?

Buckeye
07-15-07, 10:45 AM
<Scratches head>

Not sure what type of monitor you are looking at. Perhaps some one who knows a bit more about this than I can post in.

But from the way I look at it is this. A 8800gtx is great and all, but unless you are planning on running a 24" LCD/Monitor or larger do you really need a gtx. You will not even see all the detail that a 8800gtx can throw at you on smaller screens.

I used to have a little 17" monitor before and playing Eve-Online, if I turned the rez up I could hardly read the text in that game, other games I had the same problem. I had a different GPU back then but same thing applies.

I mean to display what a 8800gtx is made to do and going with a cheapo monitor/LCD is kinda a waste. All that horse power and nothing to show it on. I mean you could always upgrade later on, but shoot by then they will have a whole new batch of GPU's out, who knows.

I mean it's your money, but if money that tight I would go with a 8800gts setup and build a system that can handle that really well.

SLippe
07-15-07, 12:23 PM
One thing to remember when buying a PSU...

The heavier, the better. ;)

|MaguS|
07-15-07, 12:37 PM
One thing to remember when buying a PSU...

The heavier, the better. ;)

Wasn't that your rule for women aswell?

PaiN
07-15-07, 01:49 PM
Wasn't that your rule for women aswell?

Don't ever talk smack about SLippe's women....they have no equal ;)

Elegy
07-15-07, 02:15 PM
<Scratches head>

Not sure what type of monitor you are looking at. Perhaps some one who knows a bit more about this than I can post in.

But from the way I look at it is this. A 8800gtx is great and all, but unless you are planning on running a 24" LCD/Monitor or larger do you really need a gtx. You will not even see all the detail that a 8800gtx can throw at you on smaller screens.

I used to have a little 17" monitor before and playing Eve-Online, if I turned the rez up I could hardly read the text in that game, other games I had the same problem. I had a different GPU back then but same thing applies.

I mean to display what a 8800gtx is made to do and going with a cheapo monitor/LCD is kinda a waste. All that horse power and nothing to show it on. I mean you could always upgrade later on, but shoot by then they will have a whole new batch of GPU's out, who knows.

I mean it's your money, but if money that tight I would go with a 8800gts setup and build a system that can handle that really well.

There are many games out there (like Oblivion for instance) that have fairly low fps even at 1280x1024 and the gtx provides ~40% improvement in these games over the gts (30 -> 42). 30fps is barely playable whereas 42 is much more pleasant. Furthermore, the resolution may be smaller but the screen size is also smaller - dpi is roughly unchanged for monitors regardless of size so I doubt I'll notice much difference.

The 8800gtx is also generally more futureproof and my monitor can't be bigger than 19" anyway because it will be too much hassle to ferry to and from university during holidays. Besides, when I return I'll be plugging in the system to my old 17" CRT which has a maximum resolution of 1600x1200 on a 16" viewable screen!

Eltigre88
07-16-07, 07:27 AM
I see that it has dual +12 rails. Now this is good normally but if your PSU is like mine which has a dedicated rail to the CPU then your graphics card is not going to like it very much. They recommend 28Amps for the GTX so you see where 18 mite be not so good. Hope this helps.

Elegy
07-16-07, 09:56 AM
Good news, Evesham say they can upgrade the PSU to the "Thermaltake ToughPower 850W" which seems far more than enough to power my system (and probably any system until 2015).

Joe Public
07-16-07, 06:11 PM
Your planned system won't draw more than in the neighborhood of +/- 300W at worst, so yeah, it's a PSU you can take with you to your future system(s).