the machine i have built is an Intel OverDrive 486 100mhz running with a 2x 50mhz clock speed on a CH-498B v1.0 motherboard with 4mb of ram (30-pin simms), an 85mb hard drive, VESA cirrus logic gd-5426 svga card, yamaha opl 701f soundcard (WSS), running MS-DOS 7.1 (WINDOWS 98 DOS). this computer has no LPT or COM ports. i am trying to use this machine to make a mp3 box. currently i got the boot time down to 15secs :-p. i am using MPXPLAY 1.42.7 using the slow computer commands. but every 3 seconds this is a little split second jitter. i am running only himem.sys in the config.sys file and the soundcard driver in the autoexec.bat file. i have tried using an ESS AudioDrive 688 and it does the same thing. I foolishly gave away my SB16 card... my question is, is there a TSR that i can load at boot time that with keep the cpu usage down a little? or any other ways to improve performance? thanks

Just a wild guess, but watch the disk drive led and see if it blinks at about the same frequency as the sound glitch. If so, the problem could be the slow and unbuffered disk access. Under MS-DOS, disk access is through BIOS and uses direct program access, not hardware DMA. So it uses 100% of the processor to read the next record from the sound file (if not loaded into memory first). On these old machines/DOS, the sound card can not buffer enough data to play through the long and slow disk access time. One way around this is to use SMARTDRV.exe to act as a read-ahead disk buffer. (which might be a problem with the DOS 7.1 from Windows).

You state you want to keep the cpu usage down a little. Surely the opposite is required and you want to speed up processing as much as possible, or have I misunderstood? I would have thought increasing the memory from 4mb to 16 or 32kb would be a start. This increase can be used for increased buffering and processor usage. JackG suggestion above is also good. Good luck - keep us posted.

your rite jackG, it does blink about the same time. smartdrv didnt really help, it just chewed the ram. i wanted to lower the cpu usage not fasten it up. i wanted to stop devices draining its power. i wanted to see how much performance i could get out of this old harware without buying new stuff. but i was tampering around b4 and got it to work jitter free! i did this by setting the system clock speed to 3x 40mhz. so i guess i overclocked it?

you do need more ram. also you need to load emm386.exe through your config.sys file to manage your memory

Who can help me? I have a 486 DX2-66. I need upgrade the bios. AMERICAN MEGATRENDS - AMBIOS (C) 1993 UMC498 FOR 80486 CHICONY MODEL: CH-498B 40-E301-001116-00111111-121593-UMC498-H: Chicony Model: CH-498B I THANK FOR THE HELP GUSTAVO - BRAZIL

Why do you want to upgrade the bios? If there is nothing wrong, it is best left alone. regards - Mike (London)