the ultimate "do i need a 24pin PSU ?" thread

[TimeKeeper]

Originally posted by: ubermann
I just want a picture of where to put what volt in the extra 4 pin.
I thread with 13 pages and no answers and 95% nonsense.
If my PSU is good enought for NF3 and X800XT PE then its good enough for NF4 no matter what you say.
Or does the chipset take 200w ?
Im sure the X850 dont take 200w more then the X800XT PE.
I do understand the issue with PCI-E cards without the power connector.

One simple picture showing what volt the pins should have, anyone ?

HERE it is~~~~~~~~~~
http://home.comcast.net/~teamgu/Pinmod.JPG

 

[jac0b84]

srry for the double post

 

[jac0b84]

I recently installed a Sunbeam NUUO 550 in my rig and had some problems with the 6 pin PCI-e connector. This is a modular PSU and there is a 6pin to 6pin connection that I hooked up to my 6800 gt. That end of the card began to overheat and my graphics intensive applications would not run very well. I immediately unplugged the 6pin connector figuring I overlooked an incorrect compatibility between the power coming out of the PSU on that 6pin. I know that a simple solution to this would be two molex connectors and an adapter, but i had two questions before i created more clutter in my wiring. Also my rig is working seemingly fine without this extra power connection to my GPU. Is the 6pin connector necessary when I have a 24pin PSU to MOBO connection? Is anyone familiar with the 6pin connection coming out of this specific PSU?

Thanks guys

 

[Kaabi]

I think you should have it.

 

[mi1stormilst]

Just upgraded to a BFG 6800GTOC PCI-E and a Asus A8N SLI Deluxe, using my old 430W Antec with a converter, 1 day of solid gaming and so far no problems.

Have two optical drives, two raptors in raid 0, also internal USB reader, floppy, soon adding 2 320GB WD-SD's in Raid 1.

 

[SciFiJoe]

Originally posted by: Roomraider
Under heavy SLI gaming conditions my rig would shut down in less than 5 minutes, just as if I pressed the power off button during the game. Now keep in mind these shutdowns were not system crashes or BSOD's, because there were 0 errors in the event logs.
When I built both my rigs I did lots of research, power supply was at the top of the list due to SLI power demands. I grabbed 2 Thermaltake W0049 680 watt Purepower units as soon as they hit the market. To sum it all up I spent weeks changing out different hardware and reloading OS's because I just refused to believe that Themaltake could have a bunch of brand new power supplies that would only fail under SLI mode. Thermaltake RMA'd me a new 1 and guess what? Same problem!!! I switched over to an Nvidia SLI Certified unit and never had another shutdown & I'm now able to overclock.
Problem identified (Design Flaw) Warning to SLI users, do not invest in a power supply that does not seperate the SLI connectors. Namely 7800 GTX's will pull over amps from a single 2 connector SLI line. Spend a lil more $$$$$ and buy an (Nvidia Certified SLI) power supply. Don't make the same mistake i did. Don't buy a Thermaltake!!!!!!!!!

------------------------------------------------------------------------------------------------

I was just wondering if the PS you're talking about is the one with 38 amps or the one with 52 amps. I was just starting a search on power supplies and came across the TT W0049. It sounded impressive on their web site. I went to order it though and noticed most online retailers are selling the 38 amp, ATX 12V 2.0. The TT website lists the W0049 as 52 amps, ATX 12V 2.2. Which one do you have? If you have the 52 amp model I'll be glad I didn't order it yet. Thanks and good luck in your hunt for a better PS

 

[crazyshopper5]

Not to get off topic but I found this cool site...

[spam link deleted]

The odds look pretty good too.

---

Good bye.

AnandTech Moderator

 

[echo82]

My motherboard died (P4P800) recently and I decided it was time to get some new computer parts. So I ordered the following things.

CPU: AMD 64 3700+
MB: A8N-SLI Premium
Video: XFX 7800GT

I was planning to use PSU from the existing computer. I am unsure if the PSU I currently have will be able to work with the new setup.

My current PSU:

Enermax EG-465-VE Whisper (not Whisper II) Info about this PSU
It is ATX12V Version 1.2, +12V = 33A, and has total output of 460W.

The first post metions: "All the upcoming new boards (eg. Nforce 4) SHOULD be capable of running with an "old" ATX 1.3 20pin-plug equipped PSU as well as with a new ATX 2.0 24pin PSU"

Does it make a difference that this PSU is version 1.2 instead of the suggest 1.3?

Thanks for all your help.

===============================

Update: I put everything together and everything works fine. Been running for 2 days and everything is stable.

 

[The Stigs]

Wow...not sure if anyone is still checking this thread or not. After 15 pages of replies, and learning a ton, I'm like a few other folks and wondering if the power supply that I just received will cut it or not. I'm definitely a newbie and this is my first build. Here is the system that I am going for (included are links to some specs @ Newegg):

Biostar N4SLI-A9 Mobo (24 pin connector) [http://www.newegg.com/Product/Product.asp?Item=N82E16813138253]

PNY Geforce 6600GT Video Card (http://www.newegg.com/Product/Product.asp?Item=N82E16814133129) **not in SLI mode for now, and probably not for a while**

AMD Athlon 3200+ Venice Core

1 GB PC3200 RAM

FDD, 120GB HDD, CD-RW

And eventually a TV Tuner card + DVD burner.

The critical issue is the PSU: JUST PC 450W (http://www.newegg.com/Product/Product.asp?Item=N82E16817181107)

It is rated at 20A for +12V.

Bottom line: Will this PSU cut it for my new system, or should I look at investing in a better one? I'm certainly not a power user or a big gamer, so I don't think that I'll be demanding too much out of this system. A huge thanks to anyone who can help! (P.S. I won't be overclocking this)

 

[Serrinon]

I purchased this PSU two months ago Rosewill RP500 500W:
http://www.newegg.com/product/product.asp?item=N82E16817182009

Some details: +3.3V@30A, +5V@45A, +12V@26A

I have had no problems with it, and everything is running well. But he more I read about PSU's the more I feel worried because it isn't one fo the popular name brands.

Since it has been running well is it unlikely to crap out and damage my hardware, or do problems like that just happen randomly?

Will I be able to use it when I build a new PC with an:

ASUS A8N32-SLI Deluxe Socket 939 NVIDIA nForce4 SLI X16
AMD Athlon 64 3700+ San Diego 1GHz FSB 1MB L2 Cache Socket 939
Geforce 6800GT MSI NX6800GT-T2D256E 256MB 256-bit

Thanks!!

 

[ST4RCUTTER]

Just this week I went through and upgraded my main system. This is a budget/mid-range system (just getting my bang for the buck). Running with a 20-pin 350W generic PS. It does have the 4-pin CPU power also. Here is the system


1 CDROM
1 DVDRW/CDRW
1 7200RPM HDD 200GB SATA
Gforce 6600GT
1GB Patriot DDR400
Athlon 3200+
Foxconn NF4UK8AA
Hauppage video capture card
Linksys WRT wireless NIC

No overclocking and all voltage levels within 97%. Thus far rock solid...knock on wood.

 

[chilongzhan]

does not matter whether 20 or 24

 

[Dave332]

Here's a pinout for anyone who's confused about how to connect:

http://img475.imageshack.us/img475/3840/atx0wx.gif

 

[CZroe]

OK, so I gleaned this solution from the thread... Please tell me if it is correct:
My Abit AN8-SLI has a 20-pin PSU connector and a 4-pin Amp/Molex drive connector by the PCI slots (For PCI Express stability according to the manual). This is the equivalent of a 24-pin PSU except that it doesn't guarantee that there is a second 12v rail. In addition, I have two XFX 7800GT PCI Express cards in SLI. Both deviate from the reference design in that they have Amp/Molex drive connectors instead of 6-pin PCI Express connectors. This, again, does not guarantee that my PCI Express cards are on different rails. It is also a dual-core CPU setup.

So how should I go about powering this? I decided that over-specing the PSU is the only way to go so I got a TurboCool 510 Deluxe (No SLI or mention of dual +12v rails with this model). Should I only connect the two cards and the ATX 20-pin connector or should I also connect the additional PCI Express power on the board's 4-pin Amp/Molex drive connector? As I understand it, the four additional pins are not needed if the GFX cards have their own power but since these are seperate from the ATX 20 pin connector and I have no guarantee that things are shared across 2 rails, should I connect it anyway?

I would rather connect this TurboCool to my file server that has loads of HDDs in it (And currently dual PSUs), so I would like to know if the file server's Antec Truepower 430w PSU can handle this setup too (I'd like to swap)? It's an older one with pseudo-SATA connectors but it easily predates ATX2.0 dual rail, 6-pin PCI Express/24-PIN ATX, dual-core CPUs and SLI so I don't think it was designed with that kind of +12v load in mind. I know it differs from the original in that it has a "free SATA upgrade" where they chopped off two drive connectors and included two SATA connectors that may as well have been adapters because they did not include 3.3v lines.

Do both plans sound solid or should I hold off the final build until I have a TurboCool 850 SSI for the 14-drive file server and a TurboCool 510 SLI for this setup?

Thanks.

 

[jhansman]

My Asus A8N-VM CSM would not boot with anything but PSU with a 24-pin connector. In my trials to get this board to POST, I tried to 20-pinners to no avail. Finally broke down and ran out and got an Antec SmartPower 400 and the thing booted right up. Of course, this system also is running an Athlon X2 3800+, a gig of PC3200, SATA, and two optical drives.

P.S. I spent half a day trying to get the system up with an Antec NeoHE 430W. Turned out to be a bad part and has been sent back. If you are thinking of using one of these modulars (yes, I was warned here), think again.

 

[gpgofast]

Originally posted by: jhansman
My Asus A8N-VM CSM would not boot with anything but PSU with a 24-pin connector. In my trials to get this board to POST, I tried to 20-pinners to no avail. Finally broke down and ran out and got an Antec SmartPower 400 and the thing booted right up. Of course, this system also is running an Athlon X2 3800+, a gig of PC3200, SATA, and two optical drives.

P.S. I spent half a day trying to get the system up with an Antec NeoHE 430W. Turned out to be a bad part and has been sent back. If you are thinking of using one of these modulars (yes, I was warned here), think again.

I just bought with exact same MB. Running a Athlon 64 Venice 3200+, 1GB PC3200, 250 GB Maxtor PATA, Sony DVD RW. NO problems booting with a Antec 300 watt 20 pin power supply. You may have had a bad power supply maybe???

 

[imported_ceefka]

Geez, jhansman, seems like bad luck.

I have ordered a P150 that has this exact PSU. This should be a killer PSU regarding the specs: high efficiency, stable etc.

I'll also be running a rig on an X2 3800+ with GA-K8NF9 Ultra , 2GB of PC3200, 2x Maxtor 250GB SATAII, GigaByte GV-NX62TC256D8 128 MB and a NEC ND-4551A.

When everything is in and assembled I will get back on this PSU.

 

[computer]

I'm putting a BFG 7800GT on an Asus A8N-SLI mobo for a customer and I'm hoping someone can tell me what kind of PSU I HAVE to have. Does it HAVE to be an "SLI power supply" or is that just a selling point like "cable ready" TV's?

The mobo manual says a 500W+ 25A PS is recommended for a two 6800GT cards and an FX 57 CPU. A 4400+ X2 is being used in this setup and ONE card, but like I said it's a 7800GT. So that sounds like I guess a 500w 25A would be enough as far as the mobo is concerned.

The only unusual plugs on the mobo is one called an "EZ Plug" which appears to be a standard large 4-pin Molex connector like drives use. However, according to the pin-out diagram for it in the mobo manual, instead of 5V, G, G, 12V wires like a typical connector, it calls for 5V, EZ Det, G, 12V!! What's "EZ Det"?? The manual says it's just a connector to "insure power integrity", so this is rather confusing since that EZ Det line would just be a ground. I do believe though it's only used for dual PCI-ex cards.

The BFG site says the video card MUST have AT LEAST 26A on the 12V line! http://www.bfgtech.com/7800GT_256_PCIX.html . So, that rules out ALL of the PSU's I have in stock, and means that it must be at least a 26A PS.

Sooo, this brings me back to the original question as to what PS do I have to get....can it be just a regular 24-pin PS w/26A+ on the 12V line? Do I have to get a dual 12V rail PSU? Do I have to get one that STATES "SLI ready"? One more thing, are the dual 12V rails in a PS cumulative, added together for the actual 12V amp figure? In other words, if one is 16A 12V1 and 16A 12V2, is that 32A on the 12V line and would suffice for a requirement of 26A?

I appreciate any info.
Thanks.

 

[EPZ Soldier]

Excellent thread! I was looking all over the web for info such as this! Anandtech is my new home! Thanks Flexy

 

[giz02]

About the ThermalTake W0049: INTERESTING READ!!
I'd been having the same SHUTDOWN issues as well. I checked my manual and the date code (0514) and noticed that I have the 38A version. There are SUPPOSED to be 3 independant 12v rails. According to the, 12v1 goes to the motherboard, 12v2 goes to the PCI-E cable, and 12v3 aren't really referenced. I was curious, so I pulled the unit out of my case (unplugged of course!) and was set on finding which cables belonged to which rail. My intentions were to distribute the power load of my 2x7800GTX's.

My system:
DFI SLI DR UT
57fx w/Zalman 7700 CU
2x7800GTX KO's
4x512meg OCZ Premiere
4xWD 40GB (SATA raid0)
1xWD 120GB
HiTek HDA Sound Card
2X Optical DVD Burners.

Playing some games, would shut my system OFF, as mentioned above, no BSOD, no reboot, straight shutdown. I was going to use the PCI-E cable to one of the cards and 12v3 to the other.

I used a multi meter to measure IMPEDANCE across the 12v pins. I figured, connecting one of the 12v pins on one cable and measuring impedance to the 12vpin of another cable should tell me if the the cables are on the same rail. 0 Impedance for same rail, >0ohms if it's on another rail.

I was alarmed to find out that the 24 pin power connector, both SATA power cables (the 4 connectors powering my HD), 2 of the peripheral cables (3 Large Molex's), AND the PCIE cable (with both PCIE Graphics connectors) appeared to be on the SAME RAIL!. 0 impedance measured across the +12v lines

The other two peripheral cables (2xlarge molex and 1FDD power) as well as the 4 pin +12v motherboard appeared to be on the other rail.

With this knowleged in hand, I connected one of my 7800's to second 12v rail with one the pcie-molex adapter supplied, and haven't had a crash since!

I remember when loading up FEAR, you could hear the PSU straining (fans were slowing down)... it sounded like it was working harder.. It was also giving off WAY more heat. Now, when I load FEAR, there is no audible difference from the PSU. It's not working as hard.

My conclusion is that there MUST have been some sort of mixup in manufactoring, and the PCIE cable is connected to 12v1 resulting in that rail being overloaded.

Let me know if this makes any sense to any of you.

I've sent them an message, but have yet to hear back!
giz

 

[thraxes]

Nice to know my Enermax with a "puny" 350W rating still is enough for a highend PCIe card, 26A on the 12V rail makes me happy.

 

[Heh]

Hello. I am new to building computers.

So let me see if I can get this right; my motherboard needs a 24 pin main power supply and a 4 pin CPU supply, so does this mean this case/PSU will have both of those to power the motherboard accordingly?

 

[computer]

Originally posted by: Heh
Hello. I am new to building computers.

So let me see if I can get this right; my motherboard needs a 24 pin main power supply and a 4 pin CPU supply, so does this mean this (http://www.newegg.com/product/product.asp?item=N82E16811144076) case will have both of those to power the motherboard accordingly?

Hey, Hey, uhhh, hey........Hello Heh. :laugh: You need to fix the link in your post. (Good idea to do that before you post it). You have the closed ) as part of the URL so it doesn't work. http://www.newegg.com/product/product.asp?item=N82E16811144076 .

First, a case has nothing to do with the "power", that's the power supply that doesn't always come with a case. They don't give any info at all on the PS that comes with that case. If one claims a PS is "AMD/P4 power supply" that usually means it has the square 4-pin P4 (and I think Athlon) AUX 12v power connector. But knowing NewEgg's frequently erroneous descriptions, I wouldn't bet on it. The only way you can know for sure is to read the reviews on the page and see if someone mentions it, or find the manufacturer's website for the PS and check it out there.

 

[Heh]

Thank you for your reply computer!

First off, I fixed my URL and changed some wording in the first post, sorry about that. (I'm not very familiar with this forum software's code. )

I will make sure I will go to Turbolink's website (The manufacturer of this case's PSU) to and try to figure out the model and get detailed information.

Thank you!

 

[theslug]

I've read through this entire thread, but I'm still confused about one thing:

Is it generally better to purchase a PSU with a high enough amperage on one 12V rail, or is it better to get a PSU with dual 12V rails as long as enough amps are supplied when necessary?

I might need to purchase a new PSU as I think mine is failing, so would the Antec TruePower II 480W be good? Right now I've got a 20-pin mobo with a 6800GT AGP card, but if I need to replace my PSU, I may as well get one that would be good for the future when I upgrade and go SLI. My main concern is whether this model will provide enough power. If not, what other models are recommended?