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Problem: HX520W & p4c800e deluxe NIC flaps up/down constantly


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Suspected Problem Synopsys: low voltage or some similar issue on 3.3V or ? Rails causing mobo on-board NIC to reset/crash constantly.


I would like help from the guru's and the official PSU support dude, since I'm doing this post as a pre-RMA query.


Immediately after the swap of PSU w/NO other changes, my system booted and during running the system tray shows network disconnected then reconnected messages as often as every few seconds. This is what I am calling NIC flapping. The flapping caused the system to fail to connect most any traffic for more than a few seconds at a time, and may have flapped up to 5 times per minute. Load on the system did not alter the rate of flapping. To repeat, once the system started idling, the NIC still flapped.


I used the NIC's built-in tests to check if it thought it was an EPROM or cabling issue. No problem found. I swapped the 100bT cable and ports to/from my Linksys switch.

I forced the NIC to negotiate only 10 or 100bT full or half-duplex speeds. None of these steps helped.


Originally I connected the power cables to the PSU trying to split the load across the 3 12V+ rails evenly based on the understanding that the 2 PSU 'ports' farthest from the permanent wire pigtail were on a diff. rail from the middle ports. Unfortunately, even the online info I saw about which ports are which rail isn't up to date for the 520 model and I'm currently using none of the PCI-E ports, which may be the 2nd rail.


I tried moving power cables on the PSU ports a few times without luck, UNTIL I swapped all in a sort-of mirror from their last port placement.


Suddenly I am here online and able to connect without even one 'flap' up/down of the NIC in the hour since re-boot.


So while may be working and thus have 'solved' the problem, the engineer in me isn't so confident in the long term.


How do I find out the details on what Voltage the NIC needs and how the PSU ports are distributing all the relevant voltages and not just the 12V+ rails?

If I don't know this, I can't be sure the next minor hardware change won't upset the apple-cart and make the system un-usable again.


It's too bad…I upgraded to the 520 for the high efficiency, the very quiet running (it's even quieter than the Tru-380S), and the good reviews/tech info I read that meant that it should work, even though my sys is an older power spec. with a different distribution of 12V/5V/3.3V demands than current mobo's.



Hardware and OS Details:

I replaced the working (but growing noisy with an age) Antec TruePower 380S (in a Sonata case) with a brand new Corsair HX520W. HX details are Rev B2W, PC012, SN# R0701A10551016.


My system is an Asus p4c800e-deluxe, ATI x1600 512MB AGP, 1GB 2.5v RAM, 4 SATA Seagate 7200.X (.7's, .10), one IDE 7200.7, an ATI TV Elite (TP 550 chip), an old SB Live sound card, a dusty Intel 536EP modem, and a USB keyboard/mouse combo. 2 other HDD's in external USB/eSATA conn'd case's. Not in-use at time of problem. The on-board NIC is an Intel 82540EM CT 10/100/1000 model. I do NOT overclock and all voltages are default in BIOS. I have shutdown unneeded ports in BIOS (COM, Parallel, Game), but I have no idea if this lessens the load the board draws for these old design devices that likely don't support power saving.


I started the issue with 11.2 NIC drivers, and changed to the just released 12.0 drivers (from Intel), without impact on the problem.


The system hardware and software prior to the PSU change was stable and never gave me ethernet interface problems. In fact, I've often run it as a server 7x24 for over 30 days uptime for most of the last 2 years. Windows XP SP2, patched, blah, blah. Windows power settings set to spin down HDD's after 5 min, and they do.


According to my calculations and past experience, I am no where near taxing this PSU unless I am doing on some line other than 12V+.


I could tear into the system again later to itemize what hardware is on which port, but I'd likely need a day or three to get to it.




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Jeff if its working I would leave it alone and most of the questions would have to come from the MB maker about how the MB distributes the power.

But I would try and reset the Bios and then load setup defaults if the problem returns. However the HX520W should have more then enough power for your system.

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