I would use another psu

Interesting, will modern ATX power supplies work with older computers? I have a tested, good modern PSU with all the right power plugs on it, just nervous about plugging it into my Pentium 3

I would do next steps :
-Try another PSU
-Try to clean graphics card contacts
-Try graphics card in another system

the GF4 MX cards are directx 7 so not much good for directx 8 games, that would account for poor performance though it maybe the games you're trying to run, the GF4 MX might not be up to the job, as for quake 2 opengl should give decent performance no need to use software renderer, if theres an option in the bios for "shadow video bios" or "cache video bios" disable it as it can cause performance issues with games.

another thing that can cause problems is if you install 2 different versions of the VIA 4-in-1 drivers, as there are drivers from each version that will conflict and cause problems, i think one was related to AGP/fastwrite, if you have installed 2 different versions the only fix is to format the drive and reinstall Os, tho if performance is that bad might be worth doing that anyway.

Interesting. I shelved a computer a while back with the SAME issue. Everest shows 1x all the time and the performance is crap. The card (GF4MX420) works in 4x AND is able to game/benchmark in other systems. I was guessing a possible BIOS issue, locking-out the AGP. I was trying to use a GF2MX400, but was not happening. 3Dmark doesn't even detect a 3d device (for either card). The board is a BCM GT133KT, but it is OEM in a MicronPC (model RS2100). When a get a tool for it, I'll try a new BIOS and see if it helps at all.

Hopefully someone knows about what could be going on. Our boards are from the same time period, I'd guess the solution will fix both. In my 7NJL6, the AGP shows as 1x when doing nothing and goes to 8x underload, much like my "modern" PCs do with the PCI-e speed. (shows PCI-E 1.1@x16 when nothing, 4.0@x16 under load).

I'm going to try out the power supply fix tonight, see what that gets me but not having too high of hopes. I will also try reinstalling Win98 and seeing if that brings any perf improvements if the PSU solution doesn't work. I have installed two versions of the VIA drivers, but really don't want to have to reinstall... (i've installed a lot of software on here that I don't really wanna dig the CD burner back out for...) so hopefully I don't run into any issues related to that.

knfn98 wrote on 2025-03-24, 17:44:

but most importantly the CPU is slowed down to an absolute crawl. It takes nearly 10 seconds to check ram at boot up, which usually is instantaneous with my old ATI Rage Pro 128, CPU based applications or playing a FLAC in Winamp is slowed, and really any task related to CPU processing is slowed to nothing. Quake 2's Software renderer runs better on the ATI Rage Pro 128 than it does with the nVidia card.

You're already seeing an issue with the speed of the RAM count when Windows isn't even involved yet. That has to either be a hardware problem or a strange interaction going on between the board's BIOS and this card.
Do you have any other system you can test this card in?

Have you tried a full reset of the CMOS settings? Sometimes there can be broken settings that might not even be visible in the menu (it doesn't show everything). The most thorough way to make sure all the settings are sane is to use the CMOS reset jumper (or unplug and remove the battery), and then use the menu option to load defaults.

I don't see how it could be a power issue - later cards can detect if they're not getting enough power and might undervolt/underclock themselves, but I don't think a GF4 MX can do that.
I don't think any desktop socket370 boards will dynamically underclock anything either, and as far as I'm aware if they overheat they just freeze.
Mobile P3 laptops can change CPU speed while they run, but P3 desktops don't.

AGP 1X might be another symptom, but in itself that doesn't explain the horrible performance. It shouldn't perform that far off from 4X, really.
You have a lot of symptoms suggesting something is crippling the CPU performance or spamming interrupts or something. It doesn't seem like it's just a graphics issue.

My socket-7 MVP3 board had a weird quirk in the BIOS settings where I had to enable USB for AGP to work. But I wasn't getting strange performance symptoms like yours, I just had a black screen as soon as Windows loaded the AGP driver.

I am running Windows 98SE with Unofficial SP3.

I've never used the unofficial service packs, but I've read of them causing odd problems sometimes.

VIA 4-in-1 drivers were a flaky thing for me on my MVP3 board. Once I figured out what version and options worked for me on the MVP3 I never tried changing it again. However, your chipset is a later and more mature generation so the drivers might not be as troublesome as I remember from the MVP3. I don't know what version people commonly recommend for the 694X.

Win98 is notorious for losing it's mind. Hardware/driver changes can certainly lead to that. To rule out any weirdness in that department, I'd do a fresh reinstall that never sees the ATI hardware, and just install the minimum amount of official patches/drivers necessary to test the card.
Messing around with reinstalls is easier if you can clone the drive somewhere, or have a spare drive you can swap in. One drive for NVidia and the other for ATI.
For the sake of experiment you could even try a different Windows version like Win2k/XP. I would guess XP SP2 would have reliable drivers for your board built in.