Geforce 7800GT - no picture at all

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daveuk100

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Hi all,

I've had a Geforce 7800GT PCI-E card for around 1 year, and it has always worked perfectly. However, today I started to have problems (I haven't made any changes to my PC's hardware setup).

Here are the symptoms/things I have tried:

■ I am experiencing an issue in which I do not receive ANY picture from my graphics card (the monitor says that no signal is detected).

■ The issue is somewhat intermittent. Out of 50 attempts to boot my pc, one attempt did yield success and I was able to get a perfect picture from boot all the way into Vista. The moment I rebooted, I again received no picture...

■ I've checked to make sure the graphics card is not loose, and that the power cables are correctly connected + the graphics card fan is going around

■ I've removed the battery from my motherboard, to reset the cmos.

■ I've removed all non-essential cards/hardware from my pc (i.e. disconnect dvd drives, took out sound card, extra hard drives, etc)

■ I've tested my monitor with another computer, and it works fine

■ I've used remote desktop to connect to the machine after it's booted...and I can connect succesfully, the only problem is that I get no display on my monitor.

■ I do not receive any beeps on boot (i.e. the mobo POSTs fine)


So my question is...does anyone have any ideas what the most likely problem could be? I'm guessing either my graphics card is dead, or my mobo has a problem....but i'm not sure which is most likely. The fact that I do get a display ocassionally (about once every 50 attempts at booting the machine) might indicate that the graphics card is ok?

Thanks,
Dave
 

daveuk100

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Sadly my friends aren't PC gamers, and they don't have PCI-E in their machines...

Given the previous replies, and I correct in thinking that you guys suspect the graphics card over the motherboard to be at fault for this issue?
 

hok

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Hi,

Hope I can help, but I haave had the exact same problem on my rig. I thought it was the mobo since my on board sound was not working on that mobo.

After one year, my computer would give highly distorted boot up screens and some Blank screens. It would also hang sometimes. Then I one time it just decided not to boot and I thought it was the mobo for sure. So I changed to a nice mobo and cpu. The rig worked fine for one month and didn’t crash on HL2 but then I started playing TF2 and it now crashes regularly on TF2 only. But now I know for sure it’s the 7800GT and will upgrade when the new ATI card comes out or the 8800GT. I think its just a flaky card.
 

daveuk100

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Thanks Hok, this is useful info.

I also suspect that it's the gfx card...because the machine boots up fine into Vista (I can hear the WIndows start-up sounds etc) I just get no picture on my monitor (at any stage from the moment I turn the pc on). I figure that if the motherboard was bad, I would be seeing other issues too.

I have ordered the cheapest PCI-E card I could find, and when it arrives (thursday probably) I will test it and see if I can get a picture with it. This will hopefully help confirm 100% that it's the gfx card...and I can then invest in a better PCI-E card (I didn't want to splash out on a good gfx card straight away, only to find that the mobo was at fault!).

I will let you know what happens...
 

daveuk100

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well, bad news....today I received a new (cheap) PCI-E card to test with....and the result is the same :( No signs of life from the monitor (even though the monitor works fine if I switch it to another machine).

This is really surprising, I was convinced the issue would be gfx...but I am now assuming it has to be the motherboard :(

Any thoughts?
 

daveuk100

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OK, I've ordered a replacement motherboard now (arriving Monday) - but in the meantime there has been a very interesting development...

I have another PC which is connected to the same powerstrip. Throughout all of these problems with my main PC, the second PC has worked fine...until this morning. I turned the spare PC on and I heard a loud "pop" sound, after which the PC would not turn on anymore. The motherboard light was on, but pushing the power-on button on the front of the PC showed me no signs of life. Luckily I had a spare PSU, so I swopped the PSU out and now the PC works 100% fine again.

So my question is....could this just be a coincidence (two PC's having big issues within the same week) or do you think this may also be the root of my initial PC problems (i.e. bad powerstrip?). I am starting to think that maybe I am getting power surges and the powerstrip that both of those PC's were connected to is not adequately protecting them. Admitedly the second PC's problems was easier to diagnose due to the loud "pop" noise and no signs of power....but my first PC still has the issue where it turns on fine, but I receive no picture on my monitor.

Is it possible that the PSU in my first computer was damaged in a similar way, but not quite so badly (i.e. not to the extent where the PC won't turn on...but in way that causes not enough power to the gfx card?)
 

daveuk100

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I just tried a new 650w PSU in the PC, and it did not solve the problem (still no picture on the monitor) - so I am now convinced it has to be the motherboard...

I have a new mobo arriving tomorrow, so i'll post again tomorrow evening (hopefully with good news!).
 

roadrunner197069

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So you do hear it load into Vista? I bet the first PSU went and took out the pci slot. I wouldnt use that power strip any more. Running two computers on the same power strip is pretty risky. Hopefully your house doesnt burn down.
 

daveuk100

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yay success! It was indeed the motherboard that was to blame for my no-video issue. I replaced the mobo today with a similar spec one, and my pc now works fine.

So in conclusion:

1) I believe the overall problem was that my PC was not protected by a surge protector or UPS...and that a power surge caused damage to my PCs.

2) The power surge damaged my motherboard, which was noticable due to the fact that I suddenly lost video output to my monitor.

If you have a similar problem...try the following things:

1) Check your cabling to make sure the cable between video card and monitor is ok (swop it for another cable, just in case)

2) Ensure your graphics card is correctly seated into it's slot on the motherboard

3) Try a replacement graphics card in the machine, just to be sure it's not the graphics card

4) Test your Power Supply - PSU (there are a lot of good PSU testing tools out there these days for around $15 - just google for them)

5) Take the battery out of your motherboard and reset the CMOS (your motherboard manual will explain how to do this).

6) Try another motherboard

Unfortunately, I had to go through every step before finding out it was the motherboard - but you might be luckier! Hope this helps.
 

Pintail

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Maybe one of the pins in your MOBO gpu slot was dirty or had a bent pin/wire? Dust bunnies like to hide in those slots!


 

Vampericmist

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I'm haveing this very problem with my comp. I managed to fix it for a week, by putting a new video cable on it, but now it's not working at all, and I cant figure out why, ive re-set the graphics card, ive cleaned the slots, ive hooked it up to another monitor

(Im thinking my AVG > DVI converter might be to blame, when i hooked it up to my grandmas monitor like ive done countless times, It suddently wasnt getting ANY Feed back, wasn't even saying *(no sig.)

- Brand new 3~ month old Graphics card ,really hopeing' its not the Mother bord, don't have the money to fix if its that-

-- my PC is makeing No beeping sounds on start up like it normaly does (earlyer today when i re-set it) - but the MB is lighting up

ive re-set the thing with JUST the monitor hooked up, And the graphics card pluged in, everything eles is on bord, but i have no onbord graphics card to fall back to..

I don't know how dead this form is, but - any advice will be gladly apresharated(sp)


Takeing the machine in to 4th Demention in about 3 days if i cant fix it. there *** seems to be breaking so fast now adays =\
 

Shandleyman

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This may be old but I was having a very similar issue. I ended up going into the bios and setting the primary video to the onboard video and it booted fine with my monitor plugged into my 7800 GT. I am running that setup right now even though I have been told by the world that I should set the bios video settings to PCIe and disable the onboard video.

Hope this helps someone out there.

BTW, it wasn't too long ago when the power consumption for a video card exceeded the current motherboards could provide to the card bus. This will cause an almost immediate reboot loop so there is never a displayed showed. Rarely, in this scenario, the computer will boot without the video. There isn't much you can do about that so that is likely why a mobo upgrade helped. Even a new PSU and plugging the PCIe power in wont help. What I mentioned above takes the initial boot power consumption out of the loop and still allows the card to work beyond the initial boot. I have 6 hard drives, 4 fans and a CD-Rom running from the PSU and even after removing all of them, I still had the reboot loop. If you have onboard video, try what I did.
 
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