Run speedsys and Doom timedemo (e.g. doom -nosound -timedemo demo3), then post your results.
Both benchmarks can be found at https://www.philscomputerlab.com/dos-benchmark-pack.html

Agree with sledge's recommendation.
However, "fast" back in the days of a DX2-66 might be considered "slow" these days.
Since you have a VLB card installed, running on a FSB of 33 MHz, check your VLB wait states in your CMOS setup (and also the jumper settings on your motherboard).
You should be able to tighten them up in order to achieve faster performance.
Faster memory and cache timings will also help.

Can you try Heretic and see if that runs better than Doom? They both use the Doom engine but Heretic uses Mode 13H. Some systems/cards have a hard time with Doom's Mode-X graphics.

Check for turbo jumper. On some boards you need to short it. That's why you need to check how fast the system runs at the moment with some sysinfo program. Like Speedsys or NSSI or Sysinfo...

I was trying to check your CPU jumpers, I’m having real trouble spotting J23-21 but if it’s those red jumpers - it looks like maybe it’s set for 25mhz bus. Not that a dx2-50 would be awful at Doom but the extra bus speed would certainly help everything. It looks like your set for 2-3,1-2,2-3 or if it’s thise jumpers and I’m wrong about orientation the your set for 50mhz bus. I’d try 2-3,2-3,1-2 which should be 33mhz, clock doubled to 66mhz.

This setup should be right over 20 fps in Doom, means some scenes will hit around 15 fps - can appear as "slow/terribly" to a modern eye raised up on 60fps games.

sledge wrote:

Run speedsys and Doom timedemo (e.g. doom -nosound -timedemo demo3), then post your results.
Both benchmarks can be found at https://www.philscomputerlab.com/dos-benchmark-pack.html

Attached is my speedsys doc.

I couldn't figure out of the doom test generated a doc but I saw at the end of the test it stated: "timed 2134 gametics in 3080 realtics"

kixs wrote:

Check for turbo jumper. On some boards you need to short it. That's why you need to check how fast the system runs at the moment with some sysinfo program. Like Speedsys or NSSI or Sysinfo...

I also believed I fixed the issue I was having. I found a short in the wires going my turbo button, which I didn't realized wasn't actually functioning properly.

BinaryDemon wrote:

I was trying to check your CPU jumpers, I’m having real trouble spotting J23-21 but if it’s those red jumpers - it looks like maybe it’s set for 25mhz bus. Not that a dx2-50 would be awful at Doom but the extra bus speed would certainly help everything. It looks like your set for 2-3,1-2,2-3 or if it’s thise jumpers and I’m wrong about orientation the your set for 50mhz bus. I’d try 2-3,2-3,1-2 which should be 33mhz, clock doubled to 66mhz.

I doubled check the jumpers you are talking about against the manual I found on line and this website: https://stason.org/TULARC/pc/motherboards/S/S … 19-VER-153.html. The jumpers appear to be set correctly for my processor. The way the jumpers are on the motherboard is stupid, from top to bottom they go J23, J21, J24. Please correct me if I'm wrong 😀

jesolo wrote:

Agree with sledge's recommendation. However, "fast" back in the days of a DX2-66 might be considered "slow" these days. Since y […]
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Agree with sledge's recommendation.
However, "fast" back in the days of a DX2-66 might be considered "slow" these days.
Since you have a VLB card installed, running on a FSB of 33 MHz, check your VLB wait states in your CMOS setup (and also the jumper settings on your motherboard).
You should be able to tighten them up in order to achieve faster performance.
Faster memory and cache timings will also help.

Are you able to expand on this a little more as to what settings I should be aiming for? I'm a novice when it comes to some of the technical bios settings and jumpers surrounding VLB. Thanks.

tensi0n wrote:

I doubled check the jumpers you are talking about against the manual I found on line and this website: https://stason.org/TULARC/pc/motherboards/S/S … 19-VER-153.html. The jumpers appear to be set correctly for my processor. The way the jumpers are on the motherboard is stupid, from top to bottom they go J23, J21, J24. Please correct me if I'm wrong 😀

Are you able to expand on this a little more as to what settings I should be aiming for? I'm a novice when it comes to some of the technical bios settings and jumpers surrounding VLB. Thanks.

Well hopefully someone else can weigh in, I can't tell. I wasnt expecting the odd numbering and pin1 is on the right then (if oriented like manual, CPU up, cache down?). Are you sure your motherboard is the same revision as the manual? The manual has far more bus speed options than printed on the physical motherboard.

I do think you should look at the VLB options as well - it looks like both JP33 and JP34 are closed - which indicates that you want to run faster than 33mhz and with 1 wait state. I would think with a DX2-66, you would do better matching bus speed 33mhz, and with 0 wait states.

I have VERY similar PC on my desk right now (Globalyst 510) and judging from the numbers, your machine is absolutely fine.

DOOM (max) - 26,66 FPS vs yours 24,25 FPS

My Speedsys:

Thanks everyone for all the feedback and help. After fixing the issue I had with my turbo button and going through the jumper setting (corrected the VLB jumpers), I finally have my machine running as it should. Doom now runs great.

For comparison this is my 486DX2-66 VLB system at the moment:

The same system with fastest cache timing:

However in the current setup I use a Adaptec SCSI controller and the S3 video card, so I had to increase cache timing one step, so the current setup has slightly lower memory bandwidth.

This is from my 486X2-66 using a PCI mainboard:

This setup uses a P24 486 with WB support (however here shown in WT mode). Most notable here is that the L1 cache speed is 69 MB/s instead of 55 MB/s.
So for a minor speed boost you may consider using a 0470 i486.