F.A.Q. (sort of)

Chips

I have a Sprinta with a mainboard that has no programmable oscillator, how do I upgrade from a 25 MHz to a 100 MHz processor?

Get a 33 MHz oscmod. Oscmods are little metal boxes about 10 x 10 x 5 mm³ small that control the frequency of a part. They cost about $5. Several oscmods are to be found on your mainboard. Two are placed near the 169 pins PGA, but the one that controls your system's speed is located near the original prosessor. Others control the ISA bus among others. If it is held in place by a little plastic ligature, cut that to remove the oscmod with its 4 pins from it's 4 pin PGA. Then you can put the new oscmod in.

Jumper settings?

Most questions concerning upgrading a system like this are about jumper settings for certain types of processors. I have a motherboard that has only one jumper to configure the CPU: use the mounted CPU or the socketed CPU. On later produced motherboards used in AMBRA Sprinta's are a lot more jumpers, which don't make things easier.

From Lars Johansson I got the jumper settings which made his AMBRA Sprinta able to use a ST 486DX2-80 (Cyrix), which isn't fully compatible with a 486:

CPU Jumper settings
CPU-setup	JP11	JP12	JP13	JP15	JP18	JP20	JP27
486	1-2	1-2	1-2	1-2	2-3	2-3	OFF
P24T	1-2	2-3	1-2	2-3	1-2	2-3	OFF
ST 486DX2	2-3	1-2	2-3	1-2	2-3	2-3	OFF

Cyrix says that their processors could work without any specific jumper setting and that the settings are only required to get more performance by tuning their special features which make them faster than Intel processors?

Jumpers?

The jumper settings for the clock frequencies of the old type:

Oscilator Jumper settings old type
Frequency	JP6	JP7	JP9
25 MHz	Closed	Open	Open
33 MHz	Open	Closed	Open
50 MHz	Open	Open	Closed

Also from Lars Johansson, the jumper settings for the clock frequencies of the new type:

Oscilator Jumper settings new type
Frequency	JP7	JP8	JP9	JP10	JP17
25 MHz	2-3	2-3	1-2	2-3	2-3
33 MHz	1-2	2-3	1-2	2-3	2-3
40 MHz	1-2	1-2	2-3	1-2	1-2
50 MHz	2-3	2-3	1-2	1-2	1-2

Why doesn't my DX4 work?

Per Engman could his DX4-100 only use as a DX4-75 in his AMBRA Sprinta II. Nicolaus Kedegren reported that AMBRA support didn't recommend using DX4 because of the motherboard. What bothers me is that my old style motherboard (no fancy programmable oscmod and no high-tech 7 CPU jumpers) works fine with an Intel DX4-100 OverDrive and the newer motherboards in the AMBRA Sprinta II give problems with it. Are the older motherboards better? That would be weird, downgrading to new stuff!

What kind of cooling should I get?

If you plan to get an OverDrive, pay attention to the CPU cooling. In my Sprinta using a DX4 OverDrive with an additional cooling fan the bottom two ISA slots are blocked for the use of full-size ISA cards. Installing the more expensive CPU-Cool(TM) which is only 1.27 cm high frees up the middle one. You'll have to stick it with the thermo-tape on top of the integreted cooling of the overdrive, but not in the middle because this will block your 5¼" drive bay.

What kind of SIMMs can I use?

My system is very picky about SIMMs. The best chance is to order the somewhat more expensive AMBRA memory kit.

Storage

Can I use a SCSI drive with my IDE drive?

Yes, but only booting from the IDE drive. If you set your drive to SCSI ID# 1 you can control the use of drives from the systems BIOS. With no drives installed in the system's BIOS it boots from the SCSI drive, which becomes station C. With your IDE drive installed in your system's BIOS it boots from the IDE drive. Your SCSI drive becomes station D. This is the situation when using MS-DOS. Linux users said that Linux can handle the BIOS in such a way that makes it possible to boot from SCSI and use IDE at the same time.

What are the /n and /f options for the Adaptec ASPI for DOS drivers?

They control the bus on and bus off times on the SCSI bus. They don't get the credit they deserve in the manual because they can seriously affect system performance in ISA systems with fast SCSI peripherals. So what are good settings for your system?

Tune your SCSI harddrive to highest performance by means other than ASPI, e.g. try 32-bit disk and file access in Windows 3.11, even if your Roland SCP-55 manual says to turn it off.
In config.sys, set the ASPI options to the fastest /n:15 /f:1
Play a 44k1 16-bit stereo .wav file from harddisk through your soundcard with Windows Media Player.
The sound probably gets chopped up. When the harddisk activity led lights up, the sound stops for a moment. I believe this is caused by the data-transfer rate "spike" over the ISA bus from reading from the disk, blocking the audio data stream to the soundcard.
Your objective is to get the "spike" just touching the audio stream to your soundcard so it won't sound distorted. Increase the bus off time (/f) and decrease the bus on time (/n) until your sound is O.K. and the data transfer rate of your harddisk the highest. A high SCSI transfer rate can negatively affect the performance of other parts of your system, but not dramatically. This means that /n:5 /f:8 may be better for overal system performance than /n:10 /f:16, but I haven't noticed much difference.
Installing more SCSI devices will affect the bus and a new SCSI tuning may be nessecary.

How about more than 16Mb RAM in a system with a ISA bus mastering card?

This is a problem. The ISA bus can access only the first 16Mb of RAM, so a lot of memory swapping has to take place in a system with over 16Mb RAM. This dramatically slows down disk reading over a DMA channel. The best way to solve this is to get drivers that can handle this in an intelligent way, as the Windows95 drivers do. In Windows95 you can choose the option of using only the lower 16Mb of RAM in your DMA settings. In DOS you'll have to set the DMA channel to 0.

Video

What can I do with the 26-pin Video Feature connector on my mainboard?: Some graphic boards have a connector that uses this interface to have VGA and PAL on two monitors at the same time.
What about an MPEG decoder?: With an MPEG-1 decoder you can play VideoCD on your system if your CD-ROM drive can handle it.

PCMCIA

Is it possible to use PCMCIA cards in a desktop?

Yes, there are several adapters which make it possible to use PCMCIA cards in a computer other than a laptop, as I do. You may encounter some non high-tech problems though:

a laptop is about 2" high, your desktop or even tower model pc is much higher. PCMCIA cards come with their own cable, which is usually not that long, for easy packing when you travel with your laptop. This could leave your cable hanging from your pc in mid-air, sooner or later tearing the PCMCIA connector out of the card. If you thought the PCMCIA cards were thin, the connector is even thinner, and you'll want as less stress as possible on this.

SystemSoft PCMCIA software, is that O.K.?

It works, but not perfectly. It randomly picks IRQ's and ports every time you boot your system. One day the modem is on COM2: the next day it's on COM3:, without taking the cards out of their sockets. It is also important which cards are in which sockets, because the wrong order can cause trouble in the assigning of IRQ's and ports by the drivers.

With Windows95?

Just using Windows95, you only use the included drivers. But if you want to play a DOS modem or network game using a PCMCIA modem you will need additional Card & Socket Services.

What about that IBM quad PCMCIA adapter, IBM doesn't even know it exists?

This is from the piece of paper I got with mine:

40G1041 recommended settings
Swithblock	Swithes	1	2	3	4	Value
S1	BLK1	to the left				no UNIX boot
S2	Slot adress	on	on	off	on	PS/2
S3	ROM adress	on	off	on	on	03E0-03E1
S4	IRQ	on	on	on	on	10

In Windows95 you can choose Add Hardware in the Control Panel to let the card get recognized as a PCIC compatible PCMCIA controller.

What is the Roland SCP-55?

SOUND Canvas PC Card : SCP-55

PCMCIA Type II
16-part multi-timbral, 28-voice capabilities
complete GM/GS compatibility
onboard reverb and chorus
play sound files by connecting the included audio output connector to headphones or any other audio device with a stereo mini-jack
recording sound files is made possible if you connect the not included MCB-3

Roland MCB-3

To use all the possebilities of the SCP-55 you will need the Roland MCB-3 connector box. Without this box you only have a stereo mini-jack coming out of the card. With this box you have MIDI-in, MIDI-out, stereo mic-in, line-in and line-out.

Frequently Given Answers: I don't know..