You could have 100 CPU's in that server, and DOSBox would still only use 1 CPU core.

option 6: graphics optimization & autocycle patches

MiniMax wrote:

You could have 100 CPU's in that server, and DOSBox would still only use 1 CPU core.

Exactly, and sorry if I offend you but try not to call something "stupid" if you don't understand it. It makes you look ignorant.

Codename: ICEMAN runs great on my machine, without stuttering on normal core. ICEMAN is a pretty undemanding game. I only have a dual Opteron, so # of CPUs as mentioned does nothing for DOSBox. If you had looked at your task manager while DOSBox was running, you would have seen that the load of DOSBox was all on just ONE CPU.

the prebuffer variable is depended on your soundcard.
you might want to lower or increase the blocksize as well.

The stuttering sound is in your case a problem between your own soundcard and DOSBox.

i believe ignorant are those people who are stuck in their minds that my post was related to number of CPUs.

it is not, in fact, it tries to help other people with sound stutters and fast machines, thus their problem isn't related to CPU at all.

Qbix, thanks for the explanation. It seems pre-buffer is a very important option in dosbox, i've used dosbox in three computers already and all three computers had audio stutters that i fixed by changing this setting only.

Isn't there a way to make the pre-buffer automatic? so that its no longer an option in the configuration thus dosbox uses whatever value is required for the audio to play correctly?

Well no offence, but multi-core doesn't equal more speed. All multi-core CPUs do is run many things at once if they are threaded and developed that way. However that doesn't mean they run one program faster, especially if that program isn't built from the ground up to be threaded. One of the many reasons why I feel multi-cores aren't really nessesary for desktop PCs unless everything heads that way.

Your 3800+ should NOT stutter on 10,000 cycles unless your PC has something running in the background. I have an FX-53 (equiv to a 4000 about) and I can go as high as 40,000 without stuttering so I would blame something besides Dosbox in this case. What soundcard do you have? What O/S are you running? How many other programs do you have loaded in memory? I would suggest optimizing windows before blaming dosbox if your 3800 stutters because I can pull at least 20,000 from a celeron 2.4 which is much slower.

Don't go thinking that because your CPU was expensive = massive speed. If so, you've been ripped off my friend. Unless you run many programs at once in seperate threads I don't see how a quad core is needed.

sehh well it's a bit odd.
prebuffer doesn't change that much but it introduces a small delay for the soundeffects.
try setting the blocksize to some other power of 2 to see if that differs as well.
It can't detected unfortunately . Perharps we could increase it when we detect that the sounds gets out of sync. but that would require some testing from people affected by it.

avatar_58, why are you even talking about cores? my post was about the pre-buffer. We already know everything you described, the issue here isn't the fast cpu as i've already said but my pre-buffer affects all three systems.

Qbix, here are my results:

blocksize=8192, prebuffer=10 : stutters every few seconds
blocksize=2048, prebuffer=10 : stutters every second
blocksize=128, prebuffer=10 : completely broken sound

blocksize=8192, prebuffer=100 : perfect sound but delayed a bit
blocksize=2048, prebuffer=100 : perfect sound
blocksize=128, prebuffer=100 : completely broken sound

anything else you'd like me to try?

I've had stuttering problems with some AC97 audio chips. Most work fine though. Maybe go find yourself some PCI sound card? A cheap Live! would do nicely. Get one that does real hardware audio acceleration. Not much point in upgrading sound chips if you don't get hardware accel out of it.

Look for:
Live! (not the "24-bit" one) or Live! Value
Audigy
Audigy 2 or Audigy 2 ZS, or Audigy 2 Value
Audigy 4 SE, Audigy 4
X-Fi

system 1: SB Live!
system 2: NVIDIA nForce Pro (VAPU / Sonata)
system 3: Intel AC97 chip (this is a laptop)

Based on what you said, only system 3 should have problems with its audio. Anyway, i dont believe its related to the sound cards or sound chipsets.

All my software that use audio one way or another are all working fine. I'm doing video editing, sound editing, games, applications, music playback, videos/movies you name it.

The only application that i have to tweak with prebuffers or any sort of parameters is dosbox and its the only software that has problems... *hint* *hint* 😉

sehh wrote:

avatar_58, why are you even talking about cores? my post was about the pre-buffer. We already know everything you described, the issue here isn't the fast cpu as i've already said but my pre-buffer affects all three systems.

Its only because I've seen people always make these points about "What? My CPU isn't enough?" without having any real knowledge of just how fast it is.

No worries, i'm a long time developer and i perfectly know how fast are current processors. Every time someone tells me his Windoze doesn't go fast enough, i let them play with my IBM 8086 😉

Unfortunately my system is way ahead in terms of hardware than anything current software can use.

This is a bit off-topic but oh well...

I'm currently using this machine to do video editing. Unfortunately there isn't anything that can take on 4 cpu's at the same time. Rendering happens on a single thread and as a result, on a single cpu.

I've tried to find applications that can properly take advantage of SMP, so far i've come up with nothing interesting.

I did find a bunch of funky applications, like a Chess emulature (Deep Freeze?) that could use whole gigs of memory and supports SMP and scales well at 4 cpu's.

Another application was Ultra Fractal, unfortunately while it fully supports SMP, its not a 64bit application. At least i managed to render some HUGE images in several seconds, while a friend takes a few days to do generate the same image.

A system like mine can be used for some Java applications that i'm working on (fully threaded) and running a web server + SQL server. Those are the only things that can really use the SMP at its full potential.

sorry for the off-topic.

I think the only way to get the best from multi-core CPUs is if they bundled each core with the speed of the latest single core CPUs. As of right now each core on a multi-core CPU isn't exactly blazing fast, which is probably why you aren't seeing much in the ways of results - unless of course the program is multi-threaded. 😉

Which of those three systems is the 3800+ btw sound card wise? I have audigy 2 zs without issues, but I would be wary of any onboard sound chips as they have issues all on their own.

system 1 runs an "AMD Athlon(tm) 64 X2 Dual Core Processor 3800+" with 1GB of ram, NVIDIA GeForce 6200 TurboCache(TM) and SATA RAID. It only has one PCI slot taken by the SB Live!.

system 2 is a "Dual AMD Dual Core Opteron(tm) 270" (4 logical cpu's) with 4GB of ram, NVIDIA GeForce 7800GTX and SCSI RAID and SATA RAID.

system 3 is an IBM ThinkPad A31p (P4M 2ghz, 1GB ram, etc).

I do believe there is an issue with dosbox and audio. Its the only application that has these kind of problems (not to mention its the only application that tweaks buffers or whatever).

I could not get Ascendancy to run without audio probs on a friend's system with the nforce2 MCP (w/o NVAPU). He was using the same DOSBOX build as I but it was not working right. So I know some AC97 chips are worse than others.

Just make sure you are running <80% CPU for testing cuz it will start to stutter up around there. Also try a few different builds. I like Gulikoza's build the most I think (google his nick).

Default settings should work for ya. It could also be something with the game, btw. Try all the sound options you can.

Well the reason I asked sehh is that I've tried dosbox on far weaker systems without any audio lag (not on beefy dos games of course) and on this current PC (Fx-53, Audigy 2 ZS) I get no audio stuttering even on the most advanced games with upwards of 35000+ cycles. So I don't know about blaming dosbox.

I also wouldn't count on pre-buffer because like qbix mentioned it makes a lag in sound effects. In other words you'd do an action such as fire a gun and hear the sound effect 2 seconds after the fact.

I want to blame the soundcards, but you say you have an SB Live! which is the exact card I have in my older celeron which has no sound stuttering on games up to the 94-95 era.

Any intensive virus scanners or other such programs running in the background? Try disabling them for a second and see if it helps. Some programs (like Symantec's brand) like to eat up resources and constantly scan and use CPU activity.

i can play settlers2 at 61000 cpu cycles with no audio stuttering... minus the main menu. this was acheived with both onboard ac97 and with a x-fi x-treme gaming s/c.

What's your system franpa?