Hi group, thanks for all the fantastic advice you've already posted; I've been searching your forums for the past three days, testing and trialling most everything I could.
This is going to be long; my apologies. I'm not very techie, myself, but my husband has been building his own systems for many years (and I let him do all the poking around in the important hardware).
Let's see if I can give you a semi-accurate account of what happened.
Husband and I bought new parts for his main PC as it was time to upgrade. Mobo, CPU, RAM, PSU, a second video card (same as the first), and a case with more fans than you can shake a stick at. Installed everything *except the new video card* (awaiting its arrival), updated the system, all new drivers for Win7, it was working absolutely beautifully for over a week (maybe closer to two).
Second video card gets here, installed as per instructions, bridged the SLI. Turn it on, and no video! Checked that we were doing all the right things (plugged into the correct card, all powered, everything was in the right place), decided that maybe it was just being weird, and took that card out. Since the first GPU had been perfect immediately prior, we tried to boot with it (second card taken out completely). Still nothing. Computer would power on, fans would start spinning, but there was no indication that it was getting anywhere (including no Windows startup sound through the main speakers, although the system is dual-boot Win7 and XP, so it may not have gotten to that point).
Tried some troubleshooting to no avail. Figured out that there was no case/Mobo speaker to communicate to us, and there only seemed to be an LED to complain about the RAM if it was taken out. Ducked down to the local computer place, grabbed a speaker, stuck that in.
At some stage, we tried resetting the CMOS (using the jumper switch, then much later taking the battery out), and I think that made things worse, *or* made the BIOS work properly to shut off the system due to malfunction (it might not have been registering the issue prior to CMOS reset, who knows).
When the EATX 12V is plugged in, the whole system powers down, then tries to restart. There were a few occasions where the RAM LED came on and the POST beeps gave a RAM error message. We put the RAM back in, the memory warnings turn off, but no POST VGA warnings sound. After taking the RAM back out, neither the RAM LED or POST beeps functioned.
Since the RAM LED/beeps only worked after resetting the CMOS, we tried that again. Since then, it's just been start-stopping whenever the EATX 12V is connected (not even getting to the stage it can POST).
We have cleaned the CPU and heatsink, and reapplied Arctic Silver as per instructions.
The Mobo "standby power" LED seems to work a bit wonky; sometimes it stays lit after unplugging the PSU's cord (until the LED itself uses whatever remaining power, I suppose). Sometimes it doesn't light up when the PSU is connected to the Mobo, has the cord in, has the back switch on, and will only light up once the power button is pressed. It was my understanding that it shouldn't really do that; it should light up as long as the PSU is connected and ready to go. But I'll let you decide how relevant that is.
We've done all the troubleshooting in shortstuff_mt's checklist, including breadboarding. We have removed everything apart from Mobo, CPU and PSU with power connected only to Mobo and CPU.
We've checked both GPUs in another system, they work fine.
We *did* put the PSU into a lower-power system. First attempt to boot was freezing at POST, and after screwing the PSU into the case fully, it seemed to start everything fine (perhaps grounding it?).
We haven't got access to another high-power PSU to accurately narrow it down to the CPU or Mobo.
There are no known heat problems, and the first malfunction was triggered when we installed the second PCI-E video card.
Now, before we go replacing parts, I just wanted to double-check that this isn't some kind of known issue with the Mobo or CPU, and we're on the right track by assuming the PSU was somehow at fault here.
I'd also like to know, could any of the parts have been damaged from a malfunctioning PSU?
Details about the system are as follows:
ASUS M4N98TD EVO
AMD Phenom II X4 965 Black Edition
4GB (x2 2GB) Corsair VS2GB1333D3
CoolerMaster Silent Pro M850
1TB WD Caviar Green
(x2) Zotac GeForce GTS250
DVD drive
Antec Three Hundred, with one additional fan attached
Running Windows7 and XP, fully updated drivers
Thank you all for any advice you have.
This is going to be long; my apologies. I'm not very techie, myself, but my husband has been building his own systems for many years (and I let him do all the poking around in the important hardware).
Let's see if I can give you a semi-accurate account of what happened.
Husband and I bought new parts for his main PC as it was time to upgrade. Mobo, CPU, RAM, PSU, a second video card (same as the first), and a case with more fans than you can shake a stick at. Installed everything *except the new video card* (awaiting its arrival), updated the system, all new drivers for Win7, it was working absolutely beautifully for over a week (maybe closer to two).
Second video card gets here, installed as per instructions, bridged the SLI. Turn it on, and no video! Checked that we were doing all the right things (plugged into the correct card, all powered, everything was in the right place), decided that maybe it was just being weird, and took that card out. Since the first GPU had been perfect immediately prior, we tried to boot with it (second card taken out completely). Still nothing. Computer would power on, fans would start spinning, but there was no indication that it was getting anywhere (including no Windows startup sound through the main speakers, although the system is dual-boot Win7 and XP, so it may not have gotten to that point).
Tried some troubleshooting to no avail. Figured out that there was no case/Mobo speaker to communicate to us, and there only seemed to be an LED to complain about the RAM if it was taken out. Ducked down to the local computer place, grabbed a speaker, stuck that in.
At some stage, we tried resetting the CMOS (using the jumper switch, then much later taking the battery out), and I think that made things worse, *or* made the BIOS work properly to shut off the system due to malfunction (it might not have been registering the issue prior to CMOS reset, who knows).
When the EATX 12V is plugged in, the whole system powers down, then tries to restart. There were a few occasions where the RAM LED came on and the POST beeps gave a RAM error message. We put the RAM back in, the memory warnings turn off, but no POST VGA warnings sound. After taking the RAM back out, neither the RAM LED or POST beeps functioned.
Since the RAM LED/beeps only worked after resetting the CMOS, we tried that again. Since then, it's just been start-stopping whenever the EATX 12V is connected (not even getting to the stage it can POST).
We have cleaned the CPU and heatsink, and reapplied Arctic Silver as per instructions.
The Mobo "standby power" LED seems to work a bit wonky; sometimes it stays lit after unplugging the PSU's cord (until the LED itself uses whatever remaining power, I suppose). Sometimes it doesn't light up when the PSU is connected to the Mobo, has the cord in, has the back switch on, and will only light up once the power button is pressed. It was my understanding that it shouldn't really do that; it should light up as long as the PSU is connected and ready to go. But I'll let you decide how relevant that is.
We've done all the troubleshooting in shortstuff_mt's checklist, including breadboarding. We have removed everything apart from Mobo, CPU and PSU with power connected only to Mobo and CPU.
We've checked both GPUs in another system, they work fine.
We *did* put the PSU into a lower-power system. First attempt to boot was freezing at POST, and after screwing the PSU into the case fully, it seemed to start everything fine (perhaps grounding it?).
We haven't got access to another high-power PSU to accurately narrow it down to the CPU or Mobo.
There are no known heat problems, and the first malfunction was triggered when we installed the second PCI-E video card.
Now, before we go replacing parts, I just wanted to double-check that this isn't some kind of known issue with the Mobo or CPU, and we're on the right track by assuming the PSU was somehow at fault here.
I'd also like to know, could any of the parts have been damaged from a malfunctioning PSU?
Details about the system are as follows:
ASUS M4N98TD EVO
AMD Phenom II X4 965 Black Edition
4GB (x2 2GB) Corsair VS2GB1333D3
CoolerMaster Silent Pro M850
1TB WD Caviar Green
(x2) Zotac GeForce GTS250
DVD drive
Antec Three Hundred, with one additional fan attached
Running Windows7 and XP, fully updated drivers
Thank you all for any advice you have.