PSU Requirements For Duel Socket 940 Motherboard

[Immitem]

Hello there, I am back again with another question about the same motherboard and I hope it is in the right forum section for the reasons I will give below.

My Asus K8N-DL build went together pretty smoothly but then quickly went to shit.

Motherboard: Asus K8N-Dl
CPU: 2x AMD Opteron 285
GPU: Nvidia Quadro FX 4600
RAM: 6x Kingston DDR 400MHZ 1GB
HDD: 2x 10000RPM WD Raptor 300GB SATA1
Disk Drive: CD/DVD IDE
PSU: Rosewill Valens Series 600W Gaming Power Supply, 80 PLUS Gold Certified, Single +12V Rail,

The immediate problem is that the computer will post but will often lock up before I can get into the BIOS yet I can still do a CTRL-ALT-DELETE to restart the system as long as it is a PS/2 keyboard. If I do manage to get into BIOS it is completely stable and I can make pretty much any change I want/need. Having anything plugged into the USB ports will cause it to lock up faster.

I was worried that something was broken until I began to see similar problems in other forums/forum threads being solved by simply getting a more powerful PSU. That is all fine and dandy until I saw this video by good ol'Phil:

https://www.youtube.com/watch?v=efK7mw8eYiE

I am only just learning this but it appears to show how the amperage on rails in older PSUs are skewed. This makes me wonder if it is the same story with the socket 940 motherboard not getting enough juice through the right rail on the newer PSU. Furthermore, when using PSU calculators I only just noticed that I failed to select the server option under motherboards which shoots the wattage up to the 580 watt range!

So in summery, while I cannot find the motherboard's PSU requirements it does mention in the manual that it requires ATX 2.0 standard, the PSU I have indicates it has only one 12v rail, the system is likely to draw 580 watts at load on a 600 watt PSU (oops), even when locked up I can restart the computer with a PS/2 keyboard, the BIOS itself is perfectly stable. So what gives?

Thank you for any help you can provide!

P.S. I have not had access to the computer for a couple of days so you will notice some head scratchers (why did you not bug test that?) in the notes.

Notes: *The computer will turn on the moment I flip the power-switch on the PSU but will turn on and off normally afterwards.

*Beeper beeps once.

*The jumpers all appear to be in their default positions

*The front panel audio header is the exception as I removed two jumpers from it to plug in the front panel.

*I reset the CMOS and removed the battery altogether to no effect.

*A card reader is plugged into one of the USB headers.

*The first time I turned on the PSU I accidentally had the plug for the front panel power switch one pin too far over so that the ground pin was in the positive hole on the plug and the ground was in an unused pin between the power and reset pins.

 

[4745454b]

Why are you messing with such an old system?

The older power issue was my first guess, so I'm glad I don't have to explain that to you. If it's an issue you'll want a PSU that handles the ATX 2.0 spec, or one that handles CL1 tests. (high draw on the 3.3 and 5V rails, low 12V.) I couldn't find a review on the 600W unit, but the 700W Valens uses DC-DC so it shouldn't have a problem sending lots of power down the 3.3 or 5V rail. Assuming the OCP allows for enough to be sent.

To be honest many PSUs these day use DC-DC platforms so this isn't really an issue. I'd be more inclined to think it's an old/bad board.

 

[Immitem]

Why are you messing with such an old system?

A few reasons actually.

1.Nostalgia: I got a copy of Lightwave 8 to 9.3 which were the versions I learned in highschool. They will not running on anything newer than XP (at least the drivers for the specific dongle they use).

2. Self-Limiting: On my main computer I can spend a month modeling, texturing, and rigging a 10,000,000+ polygon model with 2-8K textures. On this computer I am literally forced to be much more conservative but not so much so that I completely kneecap myself. I can spend a week or two working on a simple project, focusing entirely on the base fundamentals.

3. Novelty... Yeah, I just find the innate idea of a top of the line system (no matter how old) enthralling. XD

The older power issue was my first guess, so I'm glad I don't have to explain that to you. If it's an issue you'll want a PSU that handles the ATX 2.0 spec, or one that handles CL1 tests. (high draw on the 3.3 and 5V rails, low 12V.) I couldn't find a review on the 600W unit, but the 700W Valens uses DC-DC so it shouldn't have a problem sending lots of power down the 3.3 or 5V rail. Assuming the OCP allows for enough to be sent.

Now that I have a few more terminologies to work with I will do further research on the matter.

To be honest many PSUs these day use DC-DC platforms so this isn't really an issue. I'd be more inclined to think it's an old/bad board.

Hopefully not.

I will tinker around a bit more with it and see if I cannot find someone willing to lend me a more powerful PSU to play around with.

Thanks for the tips.

 

[4745454b]

To test the board, perhaps remove a CPU? Should lighten the load by ~60-90W. I think those boards can handle a missing CPU.

 

[Immitem]

To test the board, perhaps remove a CPU? Should lighten the load by ~60-90W. I think those boards can handle a missing CPU.

I am sitting here gobsmacked over how that never occurred to me. I will give that a try as the manual confirms that it is possible.

Furthermore, I noticed that the board has an older BIOS iteration, 1003 versus 1009, the latest released by Asus. This caught my attention after I both noticed the motherboard did not recognise the CPUs and was displaying numbers in the bottom right corner of the screen. Assuming that they were Q-Codes I grabbed an ASUS motherboard manual I had (for a modern board) and checked the codes.

No go.

Unfortunately they were not in the manual, fortunately Google was able to help me. Whenever the computer would freeze it would show the Q-Code for CPU initialisation. If it somehow made it past that it would freeze on the code for incompatible CPU. The board has an easy to to replace BIOS chip and so I ordered one cheap off of EBAY with the latest revision. Hopefully that will solved my problems but I will give the single CPU run a go as well.

 

[4745454b]

You can't flash the bios? Usually you can just flash the bios, you don't need to install another chip. If you are on 1003 and 1009 is the newest, that could be the source of your problem. I'd install new chip/flash bios first, and if that doesn't work try testing your CPUs one at a time.

Keep an eye on which CPU you pull and the ram you have in the system. These CPUs are modern and make direct connections to the ram. Each CPU needs it's own ram, so make sure you have the right ram in there and it's with the CPU still on the board.

 

[Immitem]

You can't flash the bios?

It can only be flashed using a floppy drive and disk and I do not have one yet. If I did it would not be a problem. Actually, I did have one laying around that I pulled from a computer a few years ago but it inexplicably died not too long ago. I wanted to copy the contents of an Amiga floppy for archival purposes and it just powered down, permanently.

On the other hand the reviews on newegg for the motherboard confirm that the thing acts flippin wonky and never/properly posts with two CPUs lest you have at least BIOS revision 1006!

Keep an eye on which CPU you pull and the ram you have in the system. These CPUs are modern and make direct connections to the ram. Each CPU needs it's own ram, so make sure you have the right ram in there and it's with the CPU still on the board.

I am one step ahead of you, I read through that part of the manual and know which DIMM slots to populate. I will give it a go tonight and let you know the results tomorrow/today (time zone dependent).

Wish me luck!

 

[4745454b]

Early bios. yuck. Hope you get this sorted out.

 

[Immitem]

Yup, it was the BIOS.

Worked like a charm after that but it was not without its trials and tribulations. When trying to get it to post I took out one of the heatsinks with the CPU stuck on the bottom of it. I tried to use a piece of string to wedge underneath it to pry it off but it somehow spun-a-whirligig getting thermal paste everywhere and on the thermal pins, scratching the bottom of the heatsink, and bending about a dozen pins. I straightened the pins with a credit-card and washed them off after letting the processor soak in 91% isopropyl alcohol and brushed them with an ultra-soft toothbrush. After taking a hairdryer to it and waiting a couple of days it worked without any issue.

 

[4745454b]

Dried paste can act like glue. Warming the sink up can help loosen it. If you ever pull a sink again try doing after you've ran the PC for ~30min+. I've heard stories of people using hair dryers to warm the sink up. Glad you got it fixed and working though.

 

[Immitem]

Dried paste can act like glue. Warming the sink up can help loosen it. If you ever pull a sink again try doing after you've ran the PC for ~30min+. I've heard stories of people using hair dryers to warm the sink up. Glad you got it fixed and working though.

Thanks and thanks for the tip.