i have a antec 300 case, with sli evga gtx 260 with a antec tp-750 watt power supply. today i was in the middle of a game when the computer just froze, the screen froze and my mouse was non stop flashing. And on when i rebotted the computer the graphics cards were not working, and my mouse was still non stop blicking and my keyboard was not being recognized, this is a 1.5 year build and i have not had any problems before this. My motherboard is a xfx 780i, and i think its the motherboard that went bad, but i am not sure. I dont have another computer to swap parts out to see which part is disfunctional, so i would like to get some other people opinions on what happened. I think it was the motherboard since the mouse and keyboard isnt working, and i dont think having both graphics cards fail at the same exact time is that likely expecially since i dont overclock.
Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.
Make sure you plug the CPU power cable in. The system will not boot without it.
I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.
You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.
If no beeps: Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.
At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.
The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.
A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.
This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.
If the system beeps:
If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.
Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.
Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST. At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.
Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
The 780i had overheating issues that caused bsod and ff errors do you get anything on the LED? An error code? This could also be a psu problem...or even yes...a mobo issue. Check for codes on the debug led. The tru power series is noted for being solid but anything's possible you may have lost a rail. I've seen psu's fail where everything looks right (pc turns on fans spin etc)but one rail is dead so part of the mobo is not getting power. The easiest thing would be to partswap to another pc barring that maybe the debug led can help. Do you have a case speaker? If so is it beeping an error code? The odds of both gpu's and your mobo frying out are minimal...unless....any powersurges? Do you have a real surge supressor....no not the 5 dollar wal mart outlet strip...a surge suppressor? How do you know the keyboard and mouse weren't being recognized by the os? The 780i has no on board graphics so if neither card is working....you'd have a blue/green/blank screen. i would try booting the system with one graphic's card pull one and try just one it could be just one card is bad and the nature of sli/xfire is one card supporting the first so if the primary failed.....yea. I live for troubleshooting I'd love to hear about how this works out and how it is diagnosed. DON'T PANIC.
i read the basic trouble shooting guide and theres no problems there, and im gonna try the breadboarding tomorrow. I think i might have the ff error, i did some research and alot of people with the 780i board have got this problem in the past, where the mobo says ff when theres something wrong with it. and isnt my power supply single rail? i know that the mobo doesnt recognize my mouse and keyboard, because they are all have lights and the keyboard doesnt light up, and the mouse just flashes. This is my second xfx 780i mobo, my first one had defective pci-e slots, so yeah...... I tried booting with one graphics card, and it still didnt work. I have a surge protector and the screen just stays black.
when i first built this system i didnt have all 5 fans yet, i only had 3 i did get bsod quite often, i got it about 3-4 times. >< But i always thought it was my hitachi drive that was messing up. i didnt think that the mobo could cause bsod.......
My understanding of the FF code is internal failure whether that means cpu socket pci etc I'm unaware. the one 780i I actually worked on was showing the ff error after I had tested all components and verified they were good the board was 2 weeks old and was rma'd I would think at the 18 month mark your options are limited. I would advise you to follow thru with Jsc's advice as it is definitely sound. This board showed failure at what I would consider an unacceptable rate. Newegg showed 30 out of 300 somethin reviews which puts it around 10% (this is last I looked about 3 months ago if memory serves). FYI the tp-750 has 4 12v rails. One may have failed(I would think this unlikely as I've personally never had a problem with Antec psu's in general)but everything always works until it doesn't. You nail this sucker down post back.(if you figure it out let us know how/what. I'm leaning towards mobo as it is the weakest link in your rig(at least of the components listed.)
EEEk the dreaded 780i, i too had one of these, and by god did it cause me none stop trouble and headaches, in the end the easiest solution was sell it on ebay for spares and repairs, and then i went out and bought a whole new AM3 system, since then its been happy days.