Doom on a 486DX

[Eudimorphodon]

As I already said, that depends on whether or not Doom uses 16-bit samples and/or higher sample rate on the SB16 (there's your hardware difference). I don't know what it does exactly. In theory it could.

Well, like I said the samples are all hardcoded as 8-bit 11k so if it is using 16 bit samples when it "detects" a Soundblaster 16 (and it would have to be *detecting* one since you can't choose) it must also be using software to "upscale" them somehow.

(And, again, since you can't choose the only way the OP would have to "force" SB Pro instead would be to swap cards.)

 

[comradesean]

The DX2-66 I ordered came in and it's recognized by the system, but not the case display, I think I need to play with the jumpers on it?

Unfortunately, the faster cpu has had zero effect on the issues I was having with Doom. Smooth without sound, but jittery and nearly unplayable with. If I could see the fps, I'd guess it'd be nearly identical before and after.
Because of some shipping issues, I had to order another set of sram cache, but I'm now waiting on that, extra memory and a different soundcard without PNP to be delivered.

 

[SpidersWeb]

Yes, the case display doesn't actually measure or detect anything, it's just a light that is configured with jumpers.
On a 486 I generally set the turbo mode to the frequency of the processor (66) and set the turbo off to "Lo" - many others just use HI and Lo, but I like the number, no matter if it's pointless

modem7 put up a great page that can help with jumpers - http://www.minuszerodegrees.net/led_speed_display/led_speed_display.htm

The last one I did I just guessed, but it took quite some time.

Different sound card sounds like a good plan.

 

[Eudimorphodon]

A different soundcard without PNP to be delivered.

Hrm. Maybe I missed where PNP was mentioned earlier. Are you positive that the configuration of the sound card in terms of chosen IRQ and DMA settings actually matches your BLASTER DOS environment variable? I remember some weird stuff going down when that wasn't set up right with my SB32 PnP back in the day, but it's been too long ago to be very specific.

 

[comradesean]

Hrm. Maybe I missed where PNP was mentioned earlier. Are you positive that the configuration of the sound card in terms of chosen IRQ and DMA settings actually matches your BLASTER DOS environment variable? I remember some weird stuff going down when that wasn't set up right with my SB32 PnP back in the day, but it's been too long ago to be very specific.

Yeah, I matched it up with the settings given by the creative pnp manager. Was mucking around with Elder Scrolls Arena so I already knew what the settings were by heart. I did try it both with and without the manager being run and environment variables being set as I usually run doom by booting with the shift key held down.

 

[comradesean]

Got my replacement Sound Card in the mail. I hooked it up and got it running, but the slowdown in Doom is still there.
I fiddled with the IRQ and Address, but performance didn't change. I also have a NIC installed, but removing it didn't change anything. (Heard there might be an IRQ conflict.)

Waiting on extra RAM and sram cache now.

 

[comradesean]

Adding cache worked! I noticed when I was looking at the jumpers it was actually already configured for cache. Maybe that caused some slowdown as well?
It's still a teensy bit choppy maxed out, but I'd say it's definitely in the 30fps-ish range which is what I was expecting.

While I'm writing this, I've got some questions regarding my controller card and my CF card reader. What originally got me to crack down on this system is that I discovered my CF Card was corrupting my partition rather slowly during usage. I "resolved" this by switching it from the furthest connector on the cable to the closer one and it's so far been fine. *taps on wood* Though, It's caused me to be paranoid and run checkdisk before every shutdown. Anyone know anything of this issue?

And the last thing is that Sierra's CPC Copy Protection hangs my system. I've tried running it with Turbo enabled and disabled and both 5.25'' and 3.5'', but nothing seems to work. When I was having the issues with my CF Card Reader I would sometimes get errors during boot about my controller card, etc. (Can't remember what they were off the top of my head) Could this be related and or just be a problem with my controller card?

 

[pearce_jj]

Adding cache worked! I noticed when I was looking at the jumpers it was actually already configured for cache. Maybe that caused some slowdown as well? It's still a teensy bit choppy maxed out, but I'd say it's definitely in the 30fps-ish range which is what I was expecting.

CPU cache is entirely a processor hardware thing; the cache would be unconfigured due to being not detected by the CPU I guess. It wouldn't work at all in any other state since a cache hit would always return nothing (probably FFh).

While I'm writing this, I've got some questions regarding my controller card and my CF card reader. What originally got me to crack down on this system is that I discovered my CF Card was corrupting my partition rather slowly during usage. I "resolved" this by switching it from the furthest connector on the cable to the closer one and it's so far been fine. *taps on wood* Though, It's caused me to be paranoid and run checkdisk before every shutdown. Anyone know anything of this issue?

CompactFlash is a 3V3 or 5V CMOS standard, whilst IDE is probably 3.3V TTL on a Pentium. If your CF card adapter is set for 5V supply, the signal may be barely enough to register a high. Try your card jumpered to 3V3 supply and/or connect it directly to the Mobo header using a cable-less CF adapter. Some CF Card adapters also have VERY poor voltage regulator implementation, meaning at 5V the card actually sees about 4.3V.