Major Graphic Problem

:cry Hi,

My pc has been behaving strangely for a few weeks and now will not go past the post screen. I think it is the graphic card but want to make sure before I replace it.Although the nVidia 6800 GT 256 mb that is in there is only 2 years old.

I started to get blocks of colours showing up on screen in game and on the windows desktop.Then I would get a blue square where the mouse pointer should be on screen. The colours were all bright blue, pink, and green etc and different sizes. Areas of the desktop would vanish to be replaced by blocks of pink and blue.

Then it got worse and on the desktop and the windows startup screen it looked like there were lined impressions of circuit boards,and the blocky squares.

I have been getting weird giant pixel's in game with object's redrawing in strange triangular shapes.Then I could not set the colour quality settings as there were suddenly no options other than a very basic 8 bit setting?!

My computer had been set at 1024x768,32 bit colour quality settings,72 mhz refresh rate.

I have an Athlon XP 2800+ CPU,MSI nForce 2 Platinum motherboard,1 gig ocz ram,windows xp,direct x 9.0c. All my drivers were up to date.

I really need help here and all thought would be very gratefully received.Thanks.

Karen

 

First, I would start by pulling out your graphics card and checking that the card has no discoloration. If it is discolored, or hot to the touch, after pulling it out of your case, this could mean that there is a heat problem.

Next, see if the fan (if applicable) turns. To check the fan, just use your fingers to see if the blades spin.

Check the case for dust. If there is build up of dust, use a vacuum that and PC cleaning attachments (found at best buy, staples, etc.) to suck it all out of there.

Carefully reseat the graphics card, and see if the fan works when plugged in.

Let me know how this goes and we will go from there.

 

Hi,

Thanks for getting back to me! I have checked the fan and it is turning fine,and reseated the card.Still no go.All the fans in the system are spinning fine.

I had vacuumed out the dust already as I thought about that when I first started getting problems.

The card itself does not look discoloured. One thing I forgot to mention before was that I replaced the cpu last year as it had overheated due to it's fan malfunctioning. Do you think it could have overheated the graphics card? I was thinking that it was more likely to have caused a problem with the motherboard.

Do you think though that what I am describing sounds more like the graphics card?

 

Ok, I'll have to do a little research here...

Who makes your graphics card? Have you ever tried to overclock it? Is this an AGP card or PCI-E?

Another thing to try is to try to borrow another card from someone else and see if that one works.

Have you tried going into the device manager, and checking it there?

 

Hi,

My graphic card is an nVidia 6600 GT 256 mb ,and I have never overclocked it.I can't get into properties right now as it won't now go past the post screen.It starts the windows xp screen and then the monitor shuts down. At the moment I am posting from a friends pc. And it is an AGP card as that is what my board takes.

But as I said, before it totally wouldn't work the properties section would only list 8 bit on the quality settings giving me no other option,and not my usual 32 bit settings!It had been on 1024x768 and the refresh rate was on 72mhz.

 

karen, your problem may be to do with your power supply.
Can you tell us what the max ratings are on the power supply label?
Not just the overall power rating but also the currents for each supply should be listed.
Secondly does your motherboard have onboard VGA or have you access to borrow a simpler graphics card for testing?

Studio T

 

Hi,

The power supply was fitted new last year by a technician who said he was fitting a 450 and it would be enough for the system. I can see it says output 300 w is that right?

I just checked another graphic card in there too,not such a good one an ATI 9600 256 mb and everything works. It was so nice to see a nice clear screen.

Though I can't seem to get power in all the usb ports. Only 2 will work on the back of the machine. I think the power supply should be higher?

Thanks for all the help so far your advice has been great! I am not sure I am done though regards the power of the system.

 

Karen,
It's not the raw power output that counts with a psu. Most times when I measure power drain it is less than half the psu rated output.
However modern graphics subsystems, onboard or on card, draw huge currents. hence the new spate of auxiliary power connectors. If your psu can't supply the required current the graphics subsystem will struggle.
It's true the psus that can cope tend to be specified at greater than 450 watts so your 300 sound lightweight, but the current ratings will tell all.
The fact that another card works suggests my diagnosis is correct unless the card is faulty.

If you go into the bios (setup) you will find you can turn on or off various usb ports at front and back. The total current available from all usb ports is rather limited though.

Studio T

 

Hi,

Thanks I will check out the bios settings for the usb ports. I am pretty good with computers but electrics are not my thing!Which is why I got a repair guy to fit a new Psu ,and as the one I had was faulty last year he nipped out and purchased the new one. Perhaps he didn't pay attention to how juicy my card was in terms of power?

The pc seems stable now and is running good but I don't want it ruining either the graphics or the motherboard. I thought before it might be the cpu as it was 5 years old, and so I had just fitted a new athlon xp socket A 2800+ which I ordered last week.Slightly faster than the old 2600+ that was in there and replaced the cpu fan while I was at it.

The graphic card I took out (nVidia 6800 GT)I just tried in my brothers machine which has a 600 w psu and the card works fine. I guess I'd better buy a new psu.What kind of wattage do you think I will need? Many thanks.

Karen

 

nvidia list the minimum as 450 watt see:

http://nvidia.custhelp.com/cgi-bin/...nMuc2VhcmNoX25sJnBfcGFnZT0z&p_li=&p_topview=1

My service tables say

GEforce 6800 uses GDDR3 memory and requires 480 watt power supply and two separate molex power connectors.

Studio T