The Dual Rail v. Single Rail Challenge

[hytek369]

nice post

 

[FastEddie]

Originally posted by: jdogg707


Over the weekend I will do the following test:

P95 running at Highest Priority - 36 Hours

3DMark 2005 - 10 runs once every twelve hours

This should provide me with an accurate pircture for each PSU. I'll test outputs during 3DMark and at regualr intervals. I'll most likely just create an excel file with the data and anyone who wants it can download it from here once it is done.

I'll also try the program linked above and see what it does. The chipset fan died on my A8N today and I need to get thar replaced before I start doing any hardcore benchmarking.

This should be a very good test. The 3DM05 will give you an accurate look of how the psu will perform in an always on the fly gaming box. :thumbsup:

 

[slash196]

Man, both of them are solid as rocks...either one would make a great PSU. And the Enermax just HAPPENS to be way cheaper...

 

[Herbz]

Im using the Noisetaker 600W and have been expirencing blue screen crashes. Iv tested my RAM with memtest and did the usual troubleshooting by unplugging all unnesesary hardware.

My RAM at the moment are in slots DIMM_B1 and DIMM_B2 which is in single channel mode and the system is stable most of the time but they should be in DIMM_A1 and IMM_B1 for dual DDR mode but i get blue screens constantly.

Could this be a power problem???? I only have one 6800GT running.
I really want to get my system runnning properly as i am missing out on alot of performance.


Here is my spec:

Asus A8N-SLi Standard Edition (bios 1003)
AMD 64 3200+ Winchester
1 Gb Corsair XMS PC3200XLPT (2 x 512)
256Mb XFX PCI-E GF6800GT (1)
600W Enermax Noisetaker PSU
Sony 16x DVD±RW Dual Layer
300Gb Maxtor Plus 10 (7200rpm,16MB) SATA HD's
2 X 80 GB Western Digital HD's
Creative Labs Audigy 2 ZS Platinum
Sony Silver 16x DVD-ROM + 48x
SilverStone "TEMJIN" J02S-W Case

 

[FastEddie]

Originally posted by: Herbz
Im using the Noisetaker 600W and have been expirencing blue screen crashes. Iv tested my RAM with memtest and did the usual troubleshooting by unplugging all unnesesary hardware.

My RAM at the moment are in slots DIMM_B1 and DIMM_B2 which is in single channel mode and the system is stable most of the time but they should be in DIMM_A1 and IMM_B1 for dual DDR mode but i get blue screens constantly.

Could this be a power problem???? I only have one 6800GT running.
I really want to get my system runnning properly as i am missing out on alot of performance.


Here is my spec:

Asus A8N-SLi Standard Edition (bios 1003)
AMD 64 3200+ Winchester
1 Gb Corsair XMS PC3200XLPT (2 x 512)
256Mb XFX PCI-E GF6800GT (1)
600W Enermax Noisetaker PSU
Sony 16x DVD±RW Dual Layer
300Gb Maxtor Plus 10 (7200rpm,16MB) SATA HD's
2 X 80 GB Western Digital HD's
Creative Labs Audigy 2 ZS Platinum
Sony Silver 16x DVD-ROM + 48x
SilverStone "TEMJIN" J02S-W Case

OT: but try setting your memory voltage manually to 2.75v. Bet your problems will go away.

 

[jdogg707]

Originally posted by: Herbz
Im using the Noisetaker 600W and have been expirencing blue screen crashes. Iv tested my RAM with memtest and did the usual troubleshooting by unplugging all unnesesary hardware.

My RAM at the moment are in slots DIMM_B1 and DIMM_B2 which is in single channel mode and the system is stable most of the time but they should be in DIMM_A1 and IMM_B1 for dual DDR mode but i get blue screens constantly.

Could this be a power problem???? I only have one 6800GT running.
I really want to get my system runnning properly as i am missing out on alot of performance.


Here is my spec:

Asus A8N-SLi Standard Edition (bios 1003)
AMD 64 3200+ Winchester
1 Gb Corsair XMS PC3200XLPT (2 x 512)
256Mb XFX PCI-E GF6800GT (1)
600W Enermax Noisetaker PSU
Sony 16x DVD±RW Dual Layer
300Gb Maxtor Plus 10 (7200rpm,16MB) SATA HD's
2 X 80 GB Western Digital HD's
Creative Labs Audigy 2 ZS Platinum
Sony Silver 16x DVD-ROM + 48x
SilverStone "TEMJIN" J02S-W Case

When in DC mode, the RAM is not using anymore power, so I highly doubt it is a power issue. I would suggest doing what FastEddie said and raise the Vdimm or try another set of memory.

 

[Herbz]

 

[Herbz]

ye sorry a bit OT but its just i really want to sort this out. Tried upping the voltage but no luck.

I just read so much about dual rail PSU's being no good for this board and i have the Noisetaker 600W. You think i should get it replaced with diff PSU?

 

[Elfear]

Originally posted by: ImJacksAmygdala

I'm stuck deciding between the OCZ PowerStream 600W, OCZ PowerStream 520W, and ENERMAX Noisetaker 600W. I've heard bad things about the noise issues and availability of the PPC&C 510 SLI and I think I can get a comparable PSU cheaper.

I'd personally go with the 520W OCZ as there is just too little information out now about a dual-rail PSU's ability to keep up with (i.e. staying away from Peak usage) dual 6800 GTs/Ultras, that it's safer to go with a strong single-rail PSU. It's also the cheapest of the three at $140.

 

[ImJacksAmygdala]

Where the hell is a PSU review that covers SLI 12volt rail current? I've mentioned this to a super moderator at HardOCP and I have emailed the author of the 8 PSU roundup at the Tech Report. It's almost like review sites aren't aware of threads like these. PSU reviews are few and far between so its important that the right people know about our questions concerning SLI and 12v rail current. Xbit Labs just released a PSU review and SLI wasn't even mentioned in all 12 pages.

We should all be sending emails to Wesley Fink here at Anandtech, Kyle at HardOCP, and other well known sites like the Tech report that are known for good PSU reviews. The only way a PSU review will address this issue is if we make them aware of our concerns.

Please send a PM or email to these people...

http://www.techreport.com/forums/profile.php?mode=viewprofile&u=2

http://www.xbitlabs.com/articles/other/display/powerful-psu.html

http://www.hardforum.com/member.php?userid=90981

wesley.fink@anandtech.com <wesley.fink@anandtech.com>

http://xtremesystems.org/forums/member.php?userid=114

Let these people know you want a PSU review that uses a SLI system.

 

[jdogg707]

Originally posted by: ImJacksAmygdala
Where the hell is a PSU review that covers SLI 12volt rail current? I've mentioned this to a super moderator at HardOCP and I have emailed the author of the 8 PSU roundup at the Tech Report. It's almost like review sites aren't aware of threads like these. PSU reviews are few and far between so its important that the right people know about our questions concerning SLI and 12v rail current. Xbit Labs just released a PSU review and SLI wasn't even mentioned in all 12 pages.

We should all be sending emails to Wesley Fink here at Anandtech, Kyle at HardOCP, and other well known sites like the Tech report that are known for good PSU reviews. The only way a PSU review will address this issue is if we make them aware of our concerns.

Please send a PM or email to these people...

http://www.techreport.com/forums/profile.php?mode=viewprofile&u=2

http://www.xbitlabs.com/articles/other/display/powerful-psu.html

http://www.hardforum.com/member.php?userid=90981

wesley.fink@anandtech.com <wesley.fink@anandtech.com>

http://xtremesystems.org/forums/member.php?userid=114

Let these people know you want a PSU review that uses a SLI system.

Good info, it would be nice to see a good review of everything!

 

[FastEddie]

Curious how you're making out with the torture tests jdogg.

 

[jdogg707]

Originally posted by: FastEddie
Curious how you're making out with the torture tests jdogg.

Torture tests are going well, still haven't been able to bring the system to its knees with either one of these PSU's. The Enermax has dropped to 11.67 as the lowest 12V, but the PCP&C has been steady at a low of 11.712. I should have an excel file with all of the results by middle of the week, because some things have come up, and I won't have a chance to compile all of the data I have taken into a new file until Tuesday night or so.

On another note, I have decided to keep the PCP&C unit, as I really like the cable sleeving and the layout of the unit a little better. For anyone interested, the unit is for sale in the FS/FT forums: Enermax Unit FS

 

[Zebo]

Nice work

Couple things worth mentioning.

Your system is'nt calling for high power being stock on cards and running a winchester.

For this test to be ideal, either a prescott or Athlon-XP should be used and overclcoked.. These see 150W just on processor.. not 50-80W as your winchester is calling for.. When you start overclocking is where rubber meets the road.

Your video cards each use about 75W loaded..when you pump more current (i.e. mhz) this value can easily exceed 120W given by the following equation.

Overclocked Watts = Default Watts * (Overclocked Mhz \ Default Mhz) * (Overclocked Vcore \ Default Vcore)²

You're only running one 22W hard drive and a 34W drive.
case fans use another 5W on 12.
DVD idle -5W
Motherboard 25W

In essence your whole system, as is, only requires. 361W max on 12V rail, or 26A.. Almost any PSU would show comproable measurements. Even a 350W enermax should handle this... Both your PSU's sampled exceed this Amp rating by a large margin with 18x2 on the enermax and 36A on PCP&C.. This is why you show negliable Voltage drops/differential...


Here's the problem people have been experiancing with dual 12's.: and why I don't recommend them at all.

Since Video cards, HD, DVDs, Case fans all derive most of thier power from the secondary rail (18A in your case..much much less in most dual units) this rail is under powered when either a) overclocking Vcards b) not enough to begin with on cheaper units.. Also it defeat the whole purpose of a dual 12, isolating motherboard IC's when you're running Vcard off them... Nevertheless, overclocking Vcards it can cause random reboots or limit your OC to begin with due to being underpowered.. Add more HD's you have further problems since they suck on that same 12V line///

With a single FAT 12V line this is not an issue because thiers plenty of power to go around.

 

[Zebo]

Originally posted by: DAPUNISHER
Always nice to see members that actually deserve the 1337 title :beer: Dual rail PSUs also give some dual Opteron setups nothin' but grief so I'll be sticking with single rail PSUs myself for the forseeable future.

Same reason but on opposite end... mobo rail is underpowered.

 

[Zebo]

Originally posted by: slash196
Man, both of them are solid as rocks...either one would make a great PSU. And the Enermax just HAPPENS to be way cheaper...

Interested in price/performance? Nothing can touch this (beware a bit noisy dispite the "whisper" label)

http://www.newegg.com/app/ViewProductDesc.asp?description=17-103-456&depa=1

 

[Muhadib]

Originally posted by: boatillo
Now test the Fortron Blue Storm 500w and see how it does for $75

I've got at Blue Storm 500, but no 6800's... yet. Once the price comes down I'll post my findings. Works without any issues for my current rig in my sig.

 

[jdogg707]

Originally posted by: Zebo
Nice work

Couple things worth mentioning.

Your system is'nt calling for high power being stock on cards and running a winchester.

For this test to be ideal, either a prescott or Athlon-XP should be used and overclcoked.. These see 150W just on processor.. not 50-80W as your winchester is calling for.. When you start overclocking is where rubber meets the road.

Your video cards each use about 75W loaded..when you pump more current (i.e. mhz) this value can easily exceed 120W given by the following equation.

Overclocked Watts = Default Watts * (Overclocked Mhz \ Default Mhz) * (Overclocked Vcore \ Default Vcore)²

You're only running one 22W hard drive and a 34W drive.
case fans use another 5W on 12.
DVD idle -5W
Motherboard 25W

In essence your whole system, as is, only requires. 361W max on 12V rail, or 26A.. Almost any PSU would show comproable measurements. Even a 350W enermax should handle this... Both your PSU's sampled exceed this Amp rating by a large margin with 18x2 on the enermax and 36A on PCP&C.. This is why you show negliable Voltage drops/differential...


Here's the problem people have been experiancing with dual 12's.: and why I don't recommend them at all.

Since Video cards, HD, DVDs, Case fans all derive most of thier power from the secondary rail (18A in your case..much much less in most dual units) this rail is under powered when either a) overclocking Vcards b) not enough to begin with on cheaper units.. Also it defeat the whole purpose of a dual 12, isolating motherboard IC's when you're running Vcard off them... Nevertheless, overclocking Vcards it can cause random reboots or limit your OC to begin with due to being underpowered.. Add more HD's you have further problems since they suck on that same 12V line///

With a single FAT 12V line this is not an issue because thiers plenty of power to go around.

The major question trying to be answered here is whether a dual rail PSU can handle the load of a SLI system. I agree there are a lot of things I could do in order to increase the load on the PSU's, and am not trying to say that my system is as heavy duty a power hog as some others out there. My main tests this weekend with 3DMark 05 looping on my video cards, which I did clock at 400/1080, and Prime95 going at highest priority with maximum heat and power consumption settings, on my overclocked 2GHZ @ 2.6GHZ A64 @ 1.6V...neither PSU failed stability tests. The system got hot, and it got bogged down, but nothing failed. Either way I have suggested some new evidence with no speculation, and I will have a ful Excel Worksheet with my numbers for anyone that is interested by Wednesday.

 

[FastEddie]

That's all we were trying to see with these tests of yours----how much of a strain was placed on each of the two psu's. You've already answered my question.

 

[ImJacksAmygdala]

Any updates?

 

[destroyerjjbg]

hi what about a sli system and overclock eg the quad 12v rails like the silverstone
http://www.silverstonetek.com/products-65zf.htm

or triple rail like tt 680w


http://www.thermaltake.com/purepower/w049atx12v/w0049atx12v.htm


how they had distributing the rails for hd, cd/dvd,cpu, mems , pci-e plug,etc?
how to be sure that overcloking gpus or cpus we don`t get limetation by the max of the rail that suply it?

thx very much

 

[ribbon13]

There is only one 4-rail supply i would ever buy...
PCP&C 850 ETX
That thing is massive.

 

[DocQ]

Excellent posts. I just bought a Enermax EG375 (370W) dual +12v rail PSU. Plenty of juice on the +3.3v (30A) and the +5v (32A)... but I'm questioning the +12v rails. 12v1 (14A) and 12v2 (13A). Here's why: just put in a MSI GeForce 6600GT AGP card (replaced my nVidia MX400). System runs perfect in windows... and in 2D.. Even COD runs flawless; however, when I run 3DMark01/03/05, video freezes and system locks up.. it doesn't reboot though. I started disconnecting +12v components until I only had my boot HD and 6600GT powered.. still froze. My question is: does the AGP slot power off the same +12v rail as the CPU... or the other 12v rail (HD/opticals/etc) ? I used a dedicated molex called "Extra" to power the 6600GT.. but not sure which rail it hits?
Started getting message (from nVidia control panel) "video card cannot draw enough power.. adjusting...."

Athlon XP 3200+
ASUS A7N8X-LA nForce2 400 chipset
MSI 6600GT AGP 128
200Gb Maxtor HD
160Gb Samsung HD
ASUS 16x DVD-ROM
RICOH MP5240A DVD+RW
Floppy / 4 in 1 flash media readers / 6 USBs / 1394 ports
Enermax EG375P-VE SFMA 370W PSU

Replies greatly appreciated....

 

[ribbon13]

Thank you DocQ for providing case in point in favor of single rails.

 

[Zebo]

Originally posted by: DocQ
Excellent posts. I just bought a Enermax EG375 (370W) dual +12v rail PSU. Plenty of juice on the +3.3v (30A) and the +5v (32A)... but I'm questioning the +12v rails. 12v1 (14A) and 12v2 (13A). Here's why: just put in a MSI GeForce 6600GT AGP card (replaced my nVidia MX400). System runs perfect in windows... and in 2D.. Even COD runs flawless; however, when I run 3DMark01/03/05, video freezes and system locks up.. it doesn't reboot though. I started disconnecting +12v components until I only had my boot HD and 6600GT powered.. still froze. My question is: does the AGP slot power off the same +12v rail as the CPU... or the other 12v rail (HD/opticals/etc) ? I used a dedicated molex called "Extra" to power the 6600GT.. but not sure which rail it hits?
Started getting message (from nVidia control panel) "video card cannot draw enough power.. adjusting...."

Athlon XP 3200+
ASUS A7N8X-LA nForce2 400 chipset
MSI 6600GT AGP 128
200Gb Maxtor HD
160Gb Samsung HD
ASUS 16x DVD-ROM
RICOH MP5240A DVD+RW
Floppy / 4 in 1 flash media readers / 6 USBs / 1394 ports
Enermax EG375P-VE SFMA 370W PSU

Replies greatly appreciated....

It's about 50/50 power draw. The plug you plug in to card is the second rail.

Rail 1: is both mobo connectors (20/24 pin and P4/or 8 pin)
Rail 2: is all molex/floppy connectors

You problem is rail 1IMO.. but why guess? get a fat single 12.