Since this is in text mode it is most probably an issue with your graphics card. Which one is it?

*OOPS*

Murugan wrote:

realoldguy23 wrote:

Since this is in text mode it is most probably an issue with your graphics card. Which one is it?

I've tested with the following video cards:
NVIDIA GeForce 2 DDR Ultra 64MB AGP with DVI and VGA
NVIDIA Quadro2 Pro 64MB AGP DVI and VGA

So Murugan knows which cards are used by w0lf42? Interesting... 😉:D

Anyway, since this happens with two different video cards, my first theory of having a defective card is kind of rejected. Do 2 different cards really show exactly the same problem with the missing scan lines in text mode? Fascinating!

Lol,yes, I read it in his post. Amazing eh :p!

And I completely overlooked it in the original post despite reading it twice. Is it just my computers getting old or me too? 😉 But thanks for highlighting it!

Looks like every other line is gone. I'm not sure whether to blame the cards or the monitors... Exact same fault on both seems unlikely.

I have another monitor that I can test on -- just a little more work to get hooked up. I'll test on that.

I live near a store that sells used computer equipment. I'll pick up another video card (or two) and run more tests. I'll grab both PCI and another AGP.

Did some more testing today. Now, it's occurring via the DVI connection. I even swapped out the video card. I'll acquire more hardware and do more testing this weekend.

Are you testing it with the same monitor every time? LCD displays, especially low end ones often cause weirdness like that to happen with non-standard resolutions.

I just tested this on 3 monitors (all via VGA):

• 1 x Dell P1914S Black 19-inch 1280 x 1024
• 2x Dell Ultrasharp 1909wb 19-inch (yes, I have two of these)

Same problem happened on all three monitors.

I do have 2 x Voodoo 2 plugged in, but I am not passing the signal through them -- video signal is going directly from my AGP card to the monitor.

I ordered another motherboard and another video card to test on. I'll provide feedback when they arrive and I have time to test.

I've done more testing. But, it just seems random when the issue happens.

Here's some more oddities...

If it happens in SJGPlay (runs at 700x400), the only way to get the screen to come back (aside from reboot) is to close it and open a different program. I used to think that it had to be a different resolution. But, after opening DOSMID (which also runs at 700x400), it temporarily fixes the screen.

At one point, after running SJGPlay for a while, after the screen lost some pixels, I wiggled the analog audio cable that connects from my Yamaha MU80 into my audio splitter (which then connects to the header on my Sound Blaster Live 5.1 card). This temporarily fixed the problem.

I thought that it might be a heat issue on the video card. So, I put a 120mm fan against the GPU. But, I'm still having random issues. Some days the pixels disappear quickly and some days the display works for 30 minutes or so.

I let my BIOS screen (runs at 700x400) on for well over an hour and it never presented me with the problem.

I'm not sure if this is of interest. But, I'm connecting wires to the 40-pin header of my Sound Blaster Live! 5.1 card. I'm not having any sound issues and I don't know how this could be related. But, I can provide details of the connections if anyone thinks that this could be related.

If I'm reading your post right, you've tested this with three different monitors, two different video cards, two different motherboards, and even different video cables - and you're seeing the same issue in all cases? What haven't you changed?

Have you tried taking out the Voodoo cards and seeing if it still occurs? Maybe some kind of short to ground or voltage bleed on one of the Voodoo2s is interfering with the horizontal sync signal on the primary card, or it's interfering in the BIOS somehow. I don't even know if that's possible, but you're having a problem with every other scanline, and alternating scanline trickery is literally what SLI does. Just a thought.

Edit - slightly-more fleshed out out-of-my-ass speculation: if one of the Voodoo cards is shorting its Hsync pin to ground, and it's firing every other scanline (SLI), that could interfere with the hsync pulse on the primary VGA card as all rear ports share a common ground plane. Do Voodoo cards generate sync pulses in the background when not being used for display?

Well, I removed my Voodoo2 cards and I'm still seeing the same issue.

This weekend I'll have another motherboard and video card. I've also ordered an after-market fan (Thermaltake Crystal Orb) for my GPU which I can test next week.

I don't think my other cooling is an issue. My case has 2 x 120 fans and my CPU has a 3D printed shroud that lets me go from 50 mm (the size that came with it) to 120 mm.

I'll report back when I've tested with the new hardware.

I can recreate the issue with the items below plugged in:

• DFI CA64 REV.A1 SOCKET 370 VIA Apollo Pro133A
• 512MB PC133 133MHz 168Pin SDRAM
• INTEL PENTIUM 3 1GHz CPU
• 1F951 Dell 64MB nVidia GeForce 2 DDR Ultra AGP with DVI and VGA Outputs Video Graphics Card
• PIONEER DVD-115GA INTERNAL IDE DVD-Rom
• Quantum Fireball Plus LM30A011-01-A 3.5" 30 GB IDE Hard Drive
• Sony MPF-920 1.44MB 3.5" Internal IDE Desktop Floppy Disk Drive White
• StarTech.com 350 Watt ATX12V 2.01 Computer PC Power Supply w/ 20 & 24 Pin Connector
• 1 x CORSAIR 120mm fan
• 1 x Cooler Master 120mm fan
• Standard Case connectors (USB Header, Reset Switch, Power Switch, PC Speaker, Power LED, Hard Drive LED)

Bonus: I was also able to recreate the problem plugged into my Dell UltraSharp U2715H 27-Inch Screen LED-Lit Monitor via an AmazonBasics HL-007348 HDMI to DVI Output Adapter Cable - 10 Feet cable. Though, the monitor (which works fine on my Windows 10 system) would act as if there was no input if it was idle for more than 5 seconds -- i.e. I had to keep typing on the keyboard to refresh the screen input.

I *think* that I've solved this.

I replaced my StarTech 350 Watt PS with an EVGA 450 Watt one. I don't know if this is because of the the need for cleaner power or more power. I did purchase a TS-836A Plug Power Meter and the maximum wattage never exceeded 106. I assume moving from 350 to 450 Watt had no effect.

I ran SJGPLAY for over an hour with no issues. In my previous, recorded, tests, this caused the display issue 100% of the time -- each time failing within 30 minutes.

I did this with everything plugged in:

• Motherboard: DFI CA64
• CPU: P3 1GHz
• CPU Cooler: Stock w/ 120mm Fan
• CPU Thermal Compound: Artic MX-4
• Power Supply: EVGA 450 Watt AXT
• RAM: 3 x 512MB 168 PC-133 CL2
• GPU: nVidia GeForce2 Ultra (AGP)
• CPU Cooler: Thermaltake Crystal Orb
• GPU Thermal Compound: Artic MX-4
• GPU Cable: Generic VGA
• 3D Accelerators: 2 x Creative Labs Voodoo2 12 MB (PCI)
• Sound 1: Sound Blaster Live 5.1 SB0060 (PCI)
• Sound 2: Yamaha YMF719E (ISA)
• Network: Linksys 10/100 Etherfast 5 (PCI)
• Optical Drive: Pioneer DVD-115GA
• Hard Drive: Quantum Fireball Plus 30GB
• Floppy Drive: Sony 1.44MB

w0lf42 wrote:

At one point, after running SJGPlay for a while, after the screen lost some pixels, I wiggled the analog audio cable that connects from my Yamaha MU80 into my audio splitter (which then connects to the header on my Sound Blaster Live 5.1 card). This temporarily fixed the problem.

[...]

I'm not sure if this is of interest. But, I'm connecting wires to the 40-pin header of my Sound Blaster Live! 5.1 card. I'm not having any sound issues and I don't know how this could be related. But, I can provide details of the connections if anyone thinks that this could be related.

Looks to me as if there is some problem with badly insulated consumer stuff, or ground currents flowing through these low-voltage cables.

Which kind of electrical wiring and grounding do you have?
Is there a separate ground line, or is the ground post inside the wall outlets connected to neutral?

Looks to me as if there is some problem with badly insulated consumer stuff, or ground currents flowing through these low-voltage cables.

Which kind of electrical wiring and grounding do you have?
Is there a separate ground line, or is the ground post inside the wall outlets connected to neutral?

I think you're asking if I have a proper ground plug. This is what my outlet looks like:

As far as what is actually inside my wall, I have no idea. I have friends who are electricians. I'll inquire with them for more details.

Pretty sure bonding with the neutral was never legal under the NEC.