Author Topic: power supply (Read 523 times)

Clutz · « **on:** April 09, 2007, 02:23:36 PM »

Hello, I need some help please. My computer keeps cutting off. It will stay on until I put a load of any kind on it. Through process of elimination I am pretty sure it's either the mobo or the power supply. I'm thinking its the power supply. But I don't know what power supply to get. I have a coolmax ap 450x cx 400-b. Basically its a 450 watt psu. But what I am concerned about is the plugs and all that. I have an abit ic-7 atx mobo with p4 processor. The psu has three bunches of cables with the 4 pin connectors for ide,cd/dvd roms,etc with two of them having the little plugs for floppy drives or whatnot. It has the big plug that goes to the mobo and I think it has 20 pins. It also has a little plug that goes to the mobo that has 4 pins. It also has a connector for my sata drive. What do I look for? I don't understand the terminology used when looking at the descriptions of power supplies and as I can't hardly stay booted up long enough to study any on this matter. I hope somebody can help me please.

Thank you very much, Clutz

edit: I just found an old nvidia card and installed it thinking I could drop some load off the psu. After installing the drivers I got a message saying that the card cut its performance level back because of a low power level. I just haven't got enough power captain.

I guess I don't have enough current to keep the volts up. I still need some help on finding a psu with the proper form factor I guess you might say. TY. But, I am stable now and am going to google some . TY, Please help if you can.

Fulmar · « **Reply #1 on:** April 09, 2007, 04:22:14 PM »

Before I can recommend a power supply for you to replace your current one, I'll need to know your system specs: CPU, motherboard, video cards (both that you're using), how many hard drives, anything else.

From there we can determine what is a good power supply for you computer. It's always good to not skimp on quality for a power supply. You have to realize that the unit is supplying power to all your hardware components and shotty quality can lead you replacing a lot of parts.

As for that warning message you received after installing your older card, its because you didnt not hook up the extra 4pin molex connector (same connector as you hook up your hard drive) on the card. They made cards with these extra connector because they needed extra power that just the motherboard could not supply so if you look on the back of the card you'll see a spot to hook up another power connector.

Clutz · « **Reply #2 on:** April 09, 2007, 05:59:26 PM »

TY Fulmar. I did hook up the molex to the video card, its just not getting the juice there that it needs. You are correct about getting a good psu. I got 5 junk computers lying around here and all of them have bad psu's. Here are my specks:

P4 3.4 PRESSCOTT socket 478 cpu -800MHz bus hyper threading, 1MB cache
ABIT IC7 MOBO
1 GB DDR433 PC3500 Dual Channel Memory (two 512 sticks)
A raptor 150GB sata, and a Maxtor 160 GB 7200rpm w/ 8MB cache
Ati x850xt video card
Creative xtreme sound card
Intel PRO/1000 MT Ethernet
16X DVD+RW, and a DVD-ROM
DSL connection and Windows XP Pro.
Compaq Monitor 85HZ

This is the psu I have now: http://www.coolmaxusa.com/productDetailsPower.asp?item=CX-400&details=features&subcategory=120mm&category=single

The psu couldn't handle the upgrades I have done to this pc (cards, HD, etc). As of now, I have most of it ripped out just to keep it running. So, I guess I need to get some good, clean, stable electricity. Oh yes, I am going to build a conroe one day soon, maybe not so soon actually, so this computer will eventually be just a back up computer. Thank you very much. Clutz

Fulmar · « **Reply #3 on:** April 09, 2007, 06:22:28 PM »

This is a pretty good website to give you a rouch idea on the power supply you need (*word of caution, read below).

http://extreme.outervision.com/PSUEngine

*The power supply calculator only calculates the wattage of your system and a recommended PS rating you'd need. It's always good to go 50-100W over this recommended rating so that if you upgrade a component in the future you'll have room. Now, a lot of the newer video cards like the Geforce 8800's and the ATI R600's require a lot of amps to run the card (in this case you'll need a bigger power supply if that day comes you upgrade to a beefy video card), but the 850XT isnt that power hungry.

Your coolmax is an average brand. It's power efficiency of 65% at full load is pretty poor, so its not really a quality power supply. Generally good ones at 80% +, but you'll pay more for those.

Some of the best brands for power supply are: Seasonic (really good quality, but $$$), thermaltake (pretty good), FSP, high end Antec (their lower/mainstreams kind of suck.

The cheapest one I can recommend would be this Thermaltake one, efficiency is 65%, but for $39.99 on newegg its probably the best 'cheaper' one on there.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817153023

Now if you want one of the top of the line ones in the 400-450W range, this Seasonic at $95 is about it.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151023

Avoid this brands like the plague:
Rosewill, Apex, Just PC, Sunbeam, CoolMax, Dynapower, Raidmax, any other brand that sounds new or fishy.

If you're wanting to upgrade your processor/motherboard etc in the future, you'll probably look at a new power supply.

Clutz · « **Reply #4 on:** April 10, 2007, 04:43:08 PM »

Ty again Fulmar. I see this one from newegg:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153028

It has the PFC which I think is pretty cool, and 70% efficiency. I am also thinking the two 12v rails are a nice option as well. It's 20.00 rebate and free shipping. What I wonder about though is it shows a 24 pin connector in the pic. I need a 20 pin and a separate 4 pin. How does this work? Do I just cut off 4 pins so I can get to the other side of my mobo? Also, it says ATX 12V 2.0 version. The specks for my current psu according to newegg says ATX v2.01. Will this matter any? Here is the link for my current psu from newegg:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817159023

Thank you very much. Clutz

Sting138 · « **Reply #5 on:** April 10, 2007, 04:49:13 PM »

Clutz,

Im running an Abit AG8 Third Eye board with 3.2 P-4 and I have a Xconnect 500w psu, Works great and never had a problem with it.

Heres a link to a review on it

http://www.extremeoverclocking.com/reviews/cases/Ultra_X-Connect_1.html

Fulmar · « **Reply #6 on:** April 10, 2007, 09:54:33 PM »

Quote

Originally posted by Clutz
Ty again Fulmar. I see this one from newegg:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153028

It has the PFC which I think is pretty cool, and 70% efficiency. I am also thinking the two 12v rails are a nice option as well. It's 20.00 rebate and free shipping. What I wonder about though is it shows a 24 pin connector in the pic. I need a 20 pin and a separate 4 pin. How does this work? Do I just cut off 4 pins so I can get to the other side of my mobo? Also, it says ATX 12V 2.0 version. The specks for my current psu according to newegg says ATX v2.01. Will this matter any? Here is the link for my current psu from newegg:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817159023

Thank you very much. Clutz

That Thermaltake one says it has a 20+4 pin connector and in the pic it shows 24 pins, but with that connector, 4 pins on one side should snap off/separate to make it a 20 pin. Most PSUs have this option or they have 24 pin but have a 24 to 20 pin converter, the first option is handier.

It will work just like this in this picture:

Kev367th · « **Reply #7 on:** April 11, 2007, 10:45:14 AM »

OK I'll say it again -

It AMPS, AMPS, AMPS that matter.

No point having dual, triple, or even quadruple +12v rails if each one is low amperage.

First thing to look at irrespective of whether its a 350W, 500W or larger PSU is the amps on the +12v rail(s).

I would recommend a minimum of around 20A per +12v rail.

For an extra $20 you can get an Enermax Liberty 500W PSU that delivers 22A on each of the +12V rails.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817194003

I use one myself.

[edit] Why do I recommend 20A+ ?
Some of the video cards released in the last 6 - 12 months or so use around 16A on their own.

Skuzzy · « **Reply #8 on:** April 11, 2007, 12:26:54 PM »

PC Power and Cooling also make an outstanding supply. Pricey, but a high quality unit.

Fulmar · « **Reply #9 on:** April 11, 2007, 07:08:24 PM »

Quote

Originally posted by Kev367th

Some of the video cards released in the last 6 - 12 months or so use around 16A on their own.

Most new systems with a C2D processor and an 8800GTX/GTS are recommended at 32+ Total Amps for the system.

Clutz · « **Reply #10 on:** April 12, 2007, 03:13:48 AM »

Yes Skuzzy, TY. I have looked at the pc power and cooling site before and I like these guys. Their approach seems to have a sort of "old school" basic fundamental theory of electricity. And, new technology as well. Their comments on the web site are frank and to the point. But, as you say its pricey and this old Prescott does not deserve such an item. When I get a Conroe, pc power will be my first choice. Here is the link for anybody interested: Check out their support page as well: http://www.pcpower.com/home/

Sting138. I don't know about that X-connect you suggested. They seem like the new kids on the block. I can't find out much about them. The voltage test results on that link you gave me look good. In my way of thinking, if you put a load on a device and the volts stay up, then the amps are there to back it up, basically, not necessarily in a practical way though. I am going to investigate X-connect some more.

Fulmar. What can I say?
Thanks bud!!!! Nice screenie!

Clutz · « **Reply #11 on:** April 15, 2007, 01:53:28 PM »

I need some help again please with a psu. 7 days or so of Google, I have learned a lot and still remain quite ignorant. It seems there is a lot of confusion out there about psu's. Even the experts seem confused. At this point I am trying to figure out if I need a -5v rail and which rail (+5v or +12v) should bear the brunt what available amps my new psu should have.

My trouble is I can't figure out my mobo (abit ic7). I see that the mobo has a -5v on pin 18, but also I have read that it is not needed anymore. But I'm not sure about this. I have this snippet, a quote from Play Tool which sums up my concerns:

"Most ATX12V 1.3 and earlier PSUs provide enough 3.3 or 5 volt power to run an older motherboard but some newer ATX12V 2.0 and newer supplies have reduced the available power on 3.3 and 5. If you're using a new supply with an older motherboard then it's best to check that it has enough wattage on 3.3 and 5. You may also run into a different kind of trouble related to the -5 volt rail. -5 volt support has been optional in PSUs since ATX12V 1.3 because it's rarely used anymore. It's rarely included in new PSUs. But some old motherboards or ISA expansion cards require -5. So even if motherboards and PSUs from different eras have compatible connectors, you may have problems using them together. New and old ATX PSUs may look the same but what's going on inside is very different."

I have it narrowed down to two possibilities. One of them is this item: http://www.newegg.com/Product/Product.aspx?Item=N82E16817116001 which has lots of amps on the 5v rail (46 amps) and also has the -5v rail. But the quality of the unit is in question as it is a NZXT.

The second possibility is this item: http://www.newegg.com/Product/Product.aspx?Item=N82E16817103941 which has less amps on the 5v rail (more of it goes to the 12v rail, which is what I think my video card wants anyway) and has no -5v rail at all. But the reviews on this item seem awesome.

Please please help, any info at all would be awesome. I hate to post such drivel here in this forum, but it's u guys I trust and nobody else to much.

Thank you very much Clutz

38ruk · « **Reply #12 on:** April 15, 2007, 02:12:28 PM »

I wouldnt get to caught up in the Old motherboard thing, you stuff is a generation or so behind , but by no means old. They are prolly talking about Pentium 3 or futher back. Ive run new PSU's on older socket A Amd boards without issue , and they are quite older than your rig . GL

Fulmar · « **Reply #13 on:** April 15, 2007, 03:00:21 PM »

Clutz, check this PSU thread on the Tomshardware forums. Hopefully it will answer some of your questions.

http://forumz.tomshardware.com/hardware/PSU-101-ftopict198276.html

As for the -5v rail, ignore it if the PSU's have it or don't. Your computer won't use it as the -5V rail was stopped by Intel/AMD close to 6-7 years ago, and even then it was rarely used.

Quote from the thread above: "About 90% of the systems power usage comes from the +12v rail(s). This is why we focus so much attention on it and not the +3.3V and +5V rails. "

Now with regards to your article on the 3V and 5V rails I again would not be as concerned. Your 'guts' of your system is average to every other American PC, gaming or not, with the amount of HD's and extras etc. Now if you were run several raid/sci arrays on a server motherboard and lots of other extras, then I'd start to worry. Otherwise your worries are just that, worries.

As for the NZXT power supply. I wouldn't recommend it. I actually have a good NZXT computer case but I bought it w/o the PSU. They're more known for the computer cases than power supplies. They probably don't even make the PSU, but contract it out to a third party to make it for them, which is always 'shady.'

From the same forum and same PSU Wizard on Tomshardware, this is his PSU recommendation list. Brands and Prices as of 4/15/07

http://forumz.tomshardware.com/hardware/modules.php?name=Forums&file=viewtopic&p=1491365#1491365