Major Errors with Leadtek WinFast 7800GT

Update:

I think what he means is try updating bios and drivers. Also, is your PSU strong enough? Did you connect any extra power cables to the video card?

Just have the one little power connector it needs. 480W PSU, brand new.

Underclock it to about 70% normal speeds for both GPU and VRAM. (This reduces power consumption of the card, heat output, and may help overall).

Try changing GDDR3 VRAM timings (increase them, a BIOS flash on the Video Card to nVidia reference BIOS may help here).

Check PSU is OK (I recommend a good 550 watt PSU even for 'baseline' configurations these days)

Failing all that RMA the card.

Alright, would you possibly mind explaining how to do all that  

Grab coolbits.reg (Google it)

Go to display properties, using the classic look, under advanced, etc and you'll be able to underclock to 70% of factory GPU and VRAM (GDDR3) clock speeds.

See if this helps, and get back to us. 8)

I have the same problem with mine!
the problem is your driver ! 93.71
the driver sets my memory clock to 1500MHz !!!!
no matter what...even if i disabled the overclocking... i dont know why...
i also e-mail to nVidia but no answer!
i know that nobody believe me...but...
i cant explain it more ,just...install something like 91.47...
uninstall the driver before your Graphic Card burns :!:

Artifacts displaying on picture like mentioned, reduce speed, cool bits. If all fails do this.

Down load nibitor 3.3 use nibitor to read your bios follow the step below
here

1} Execute nibitor.exe
2} Tool, read bios, select drive, device id 00f5 (nvidia agp 7800gs), OK
3 go to tools once again and select read bios, read bios into nibitor.



Here is what I did with my bios, I changed voltages 1,2,3 all to 1.4 the reason being when ocing you want all max volts that you can possibly get away with. I have experienced in the past reduction in power if the video bios reads an error or even dx issues. Automatically the bios reads it as an error and reduces the voltages to protect the card, I’ve experienced problems with power saving cause by the system bios

CLOCK RATES you can change this to what speed you want to run

TIMINGS: Auto detects timings, test timings, settiming.
You can change the boot setting by going into the adv sign on;; Change the company to your name…….

Save the new bios to a folder or desktop.

Now read bios again and save a copy of the original bios repeat the 1,2,3 process to do this.

When you were dabbling in nibitor you are not doing anything to your bios. You are editing the information nibitor read from the video card bios.

If you want you can use nVidia Bios here and change the voltage to only 1 voltage table, also nvidia bios modifier 2 allows you to exceed the 1.4 volts, I don’t recommend this at all.
Your are ready to flash the bios,, do I or don’t I, is a scary thought, don’t blame me if something go’s wrong .WARNING! Doing this procedure without really knowing what you are doing and how to recover is not my responsibility
Download nvflash 5.33 dos and windows here you can flash your vcard bios in windows with this one. Load the modified bios at the C prompt (nvflash <filename>) to start the flash procedure, some video card are write protected at C prompt (nvflash protectionoff)if all works out you will get successfully done.
Reboot and your done

Pic's from my bios
disable fastwrite video sync

or use riva tuner and disable some pixshaders