NF4 Expert - Worked fine, now no post, LED's Flash on then off.

[computerpro3]

Hello,
I'm having an incredibly frustrating problem right now. The machine was running for 3 days PERFECTLY, at 3.1ghz with 33C under load @ 1.53v. Yesterday, I rebooted it, and it hung at the post screen. I did a hard power off, reset cmos, popped in one sitck in the 3rd orange slot, and turned the machine back on. IT posted, but gave me a CMOS checksum error. I proceeded to load up windows, where it acted REALLY slow for some reason. It was so slow that I did another hard power off, and thats where the machien died. It quite simply will not post no matter what I do.

The exact symptoms are as follows:

1. hit power button on board OR case
2. All 4 LED's flash on and off instantly once.
3. Machine just sits there and fans whir, hard drive churns a bit, and no post, no led's.

These are the things I know so far

1. Bios chip is not the problem. I swapped it out with another known good from another expert I own.

2. Power supply is not the problem. Aside from the fact it's the second best power supply in production fpr high draw systems, (it beats the pcp&c 850 for SLI configs due to single high amperage line) the voltages check out fine on the multimeter. Tried with Antec 550, same problems.

3. Watercooling is not the problem. It worked fine for 3 days, no leaks, nothing.

4. Shorting is not a problem. I installed all the motherboard standoffs correctly and nothing metallic is in contact with the motherboard.

5. Ram is not the problem. Same symptoms with the following ram, I tried all of the following as individual sticks and dual channel: 4x512mb mushkin redline xp4000 (2GB), 12x512mb OCZ Platinum pc3200 2-2-2-5, 8x512mb Corsair Valuram. None work.

6. Video card is not the problem. Despite the voltmods, it ran at 38C full load. Tried with voltmods removed and on, no difference in motherboard. Also tried one of my 7800GTX 512mbs in the board and it did not work.

7. interestingly enough, I can get the 4 leds to stay on if I unplug the 8pin connector from the motherboard. However this obviously causes the board not to post in and of itself, so its not much help.

I have all the obvious stuff done right; power connectors are all in, tried cmos reset, battery out, etc, etc.

At this point, its either the CPU or the motherboard in my opinion. It is unlikely that it is the cpu simply because it was working fine and under such superb cooling. This is supremley frustrating and I would really appreciate some help. Thanks in advance.

 

[Gagan]

The max voltage for an X2 is 1.45

If YOU'RE higher than that that's what is probably causing it.

 

[JSFLY]

Sometimes overvolting a cpu can kill it. Doesnt matter if the temps are fine or not.

Also: You will need to post your system specs.

 

[computerpro3]

Sorry, thought specs were in my sig. here they are.

Amd Opteron 146 Naked @ 3.1ghz Silver Storm G5
DFI SLI-DR Expert with Dangeden Expert Chipset Block
2GB Mushkin Redline XP4000 @ 272mhz 2-2-2-5 3.5v
BFG 7900GT @ 714mhz/1920mhz (1.55v/3.18v) Chrome Maze4 GPU
1TB odd hard drives
M-Audio Audiophile USB-> PPA2 -> Grado RS-1
Zippy 700w PSU (46a 12v line, 9lbs) sleeved and fan swapped
Silverstone TJ07/Silverstone LC18/Coolermaster ATC-101b sx-4
Rest of WC loop: Thermochill PA 120.3 (3 YL fans), 2x AQ50z pumps, dual bay ers
Monster HTS3500 MKIII Conditioning Station

And about overvolting, this is a CABNE Opteron 146. 1.55 didnt kill it, especially not under top of the line water.

 

[JSFLY]

As I said, you could be running a cpu that loads @ 10C, you put 1.7+ volts to it and you'll kill it no matter how low the temps are.

Im not saying that you killed your cpu in this situation, but I think you should try another CPU just to see if it works.

Also try a cmos clear using jumpers. Follow directions in your manual for further details. If you can go into bios -> load optimized settings and try again.

If that doesnt work, try a 8 hour then 24 hour cmos clear. Directions here:
http://www.dfi-street.com/forum/showpost.php?p=127704&postcount=24

 

[computerpro3]

Originally posted by: JSFLY
As I said, you could be running a cpu that loads @ 10C, you put 1.7+ volts to it and you'll kill it no matter how low the temps are.

Im not saying that you killed your cpu in this situation, but I think you should try another CPU just to see if it works.

Also try a cmos clear using jumpers. Follow directions in your manual for further details. If you can go into bios -> load optimized settings and try again.

If that doesnt work, try a 8 hour then 24 hour cmos clear. Directions here:
http://www.dfi-street.com/forum/showpost.php?p=127704&postcount=24

Actually that's not true; look at what the benchers on phase change run. On my phase change unit on my benching machine I run my fx-60 @ over 1.7v and its fine.....

But I do understand what youre saying and with normal cooling yes, if you shove enough voltage down a chips throat, it will die. However, 1.55v is nothing for a CABNE opteron 146 (do a search on xtremesystems and hardforums). If the chip died it wasn't from voltage. I think I'm going to have to throw my fx-60 in there and see if it works. This is really a pain in the ass, as I now have to undo the watercooling.....

 

[JSFLY]

Originally posted by: computerpro3

Originally posted by: JSFLY
As I said, you could be running a cpu that loads @ 10C, you put 1.7+ volts to it and you'll kill it no matter how low the temps are.

Im not saying that you killed your cpu in this situation, but I think you should try another CPU just to see if it works.

Also try a cmos clear using jumpers. Follow directions in your manual for further details. If you can go into bios -> load optimized settings and try again.

If that doesnt work, try a 8 hour then 24 hour cmos clear. Directions here:
http://www.dfi-street.com/forum/showpost.php?p=127704&postcount=24

Actually that's not true; look at what the benchers on phase change run. On my phase change unit on my benching machine I run my fx-60 @ over 1.7v and its fine.....

But I do understand what youre saying and with normal cooling yes, if you shove enough voltage down a chips throat, it will die. However, 1.55v is nothing for a CABNE opteron 146 (do a search on xtremesystems and hardforums). If the chip died it wasn't from voltage. I think I'm going to have to throw my fx-60 in there and see if it works. This is really a pain in the ass, as I now have to undo the watercooling.....

Quote from intel techy:

There are 4 ways that chips break:
electromigration: metal atoms in a wire move around because lots of lots of electrons hit them. Move enough metal atoms and the wire will either short with another wire, or have a hole in it and stop working.
TDDB: the insulation material that separates two key parts of a transistor breaks down creating an electrical short - which breaks the transistor. In most cases, if any one of the hundreds of millions of transistors breaks, it will break the chip.
hot-e: a key parameter of the transistor called "Vt" (threshold voltage) shifts over time - which essentially slows the transistor down. If it slows down enough, then the chip will calculate an incorrect value.
BTI: Similar to hot-e but for a different type of transistors and happens for a different reason. Usually fixed in the factory.

In all but hot-e, increasing the temperature a little makes the chip a little more likely to break (this is all statistics... there is no "do this and this will kill your chip..." it's all a matter of probability). In hot-e, lowering the temperature makes it worse.

In all of these, increasing the voltage a small amount makes them much more likely to break the chip.

As to why 10% more voltage is much worse than 10% more temperature, well let's take the example of electromigration and look at it in detail.

Read this thread for more info
http://forums.anandtech.com/messageview.aspx?catid=28&threadid=1773169

 

[computerpro3]

I'm perfectly familiar with the concept of electromigration, however, the rate at which it happens enough to kill the cpu at the voltage of 1.55 bios, 1.52v actual in a single core, CABNE opteron 146, is far longer than three days. Period. If you don't believe me, google it.

 

[Bozo Galora]

when this happens to me, I put in single stick crappy PC3200 RAM, PCI VGA vid card, reset cmos, boot to bios and set failsafe defaults
however, the fact you tried a different known good bios chip with same CRC error (I assume) does tend to point to HW failure, possibly CPU.

just make sure cmos pins not still shorted - lol