Is a Pentium II Too Fast for a DOS Rig?

Discussion about old PC hardware.

Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-13 @ 21:38

In order to keep this hobby from getting out of hand, I want to build only two rigs, a fast Win98SE rig and a DOS rig. Ideally, I would like to have a 486DX2/66 powering my DOS rig, but I'm still sourcing the parts for it.

Yesterday, I picked up a Dell Optiplex GX1 from a local surplus sale. There was a sign on it that said it was not working and was for parts only. Another buyer was surprised I was buying it because it had been sitting there for a long time, apparently, surviving multiple biweekly surplus sales. It cost $0.50.

It turned out that the hard drive was fried, but I was able to get it up and running with a spare. It has a Slot 1 Pentium II-333. I did some research into this model, and it turns out that I have the earlier motherboard revision that does not allow for upgrading the processor to PIIIs. Although the onboard graphics are AGP (Rage Pro Turbo), there three PCI slots and three ISA slots (one shared). Now that I've brought this beast back to life, I'd kind of like to keep it. I like its looks and build quality, even though it uses a Dell proprietary form factor. I like having three ISA slots.

Would this be too fast to run games from the early 90s through 96 or so? I know that some of the Epic Megagames have speed problems. I'd really want it just to play those games that have native Ultrasound support.
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby Darkman » 2014-6-13 @ 22:03

not at all , it really depends what kind of games you want to play, alot of the later more demanding games like Duke3d for instance, will actually benefit from this kind of CPU if you want to run in higher resolutions.

for the games that do give you issues (some of the Lucasarts & Sierra adventure games come to mind, Wing Commander is another notorious example) there are ways to slow down your CPU , such as turning off the L1 and/or L2 cache in the BIOS. there are also ways to deal with too much RAM , such as HimemX (although if youre only going to use it for DOS games, 16-32Mb is all you need anyways). Just make sure you get an ISA sound card of course.

as for the Epic games, the only one I know that has CPU speed issues is Jazz Jackrabbit, but there is a patch you can download (google it) that fixes this issue
User avatar
Darkman
Oldbie
 
Posts: 651
Joined: 2013-9-08 @ 10:39

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby AlphaWing » 2014-6-13 @ 23:30

Early Pentium II's are multiplier unlocked, combine that with a soft bios motherboard, so you don't have to fiddle with jumpers and you can have a slow Pentium II on a 50mhz fsb with a multiplier of 2 or a moderately fast one with its stock multiplier@66mhz fsb. Without having to constantly open the case.
User avatar
AlphaWing
Oldbie
 
Posts: 703
Joined: 2014-6-02 @ 15:34
Location: USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby Mau1wurf1977 » 2014-6-14 @ 01:41

Define "DOS Games" :)

For early DOS games I would rather go with a Pentium.
User avatar
Mau1wurf1977
l33t++
 
Posts: 7652
Joined: 2010-8-27 @ 04:15
Location: Western Australia

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby retrofanatic » 2014-6-14 @ 02:38

You may be in luck because the GX1 has a special key combination that slows the CPU speed (or maybe disables cache) on the fly. <Ctrl><Alt><\> or <Ctrl><Alt><#> (See below).

I know this because I have a couple optiplex GX series dells myself and looked this up a while ago.

Check out the the following excerpt from the GX1 manual:

Overview
Dell OptiPlex GX1 small-form-factor systems are high-speed, expandable personal computers designed
around the Intel® Pentium® II or III microprocessor. Each computer system uses a high-performance
Peripheral Component Interconnect (PCI) design that allows you to configure the computer system to your
initial requirements and then add Dell-supported upgrades as necessary.

System Features
Your system offers the following features:
An Intel Pentium II or Pentium III microprocessor.
The Intel Pentium II and Pentium III microprocessors include MMX™ technology designed to handle
complex multimedia and communications software. This microprocessor incorporates new instructions
and data types as well as a technique called single instruction, multiple data (SIMD) that allows the
microprocessor to process multiple data elements in parallel, thereby improving overall system
performance.

A keyboard command (<Ctrl><Alt><\>) that lets you switch between the microprocessor's rated speed
and a slower compatibility speed.


NOTE: This keyboard command is not available under the Microsoft® Windows NT® and
IBM® OS/2® operating systems.


CPU Speed
CPU Speed indicates the processor speed at which your system boots.
Press the left- or right-arrow key to toggle the CPU Speed option between the resident microprocessor’s
rated speed (the default) and a lower compatibility speed, which lets you accommodate speed-sensitive
application programs. A change to this option takes effect immediately (rebooting the system is not required).
You can also toggle between the rated processor speed and the compatibility speed while the system is
running in (DOS) real mode by pressing <Ctrl><Alt><\>. (For keyboards that do not use American English, press
<Ctrl><Alt><#>.)


<Ctrl><Alt><\> Toggles microprocessor speeds on 101-key keyboard (in MS-DOS® realmode only)
<Ctrl><Alt><#> Toggles microprocessor speeds on 102-key keyboard (in MS-DOS real mode only)

<F2> or <Ctrl><Alt><Enter> Starts the System Setup program (during power-on system test [POST] only)
<F3> or <F12> Automatically starts (boots) the system from the network environment specified by the Managed Boot Agent (MBA) rather than from one of the devices in the System Setup Boot Sequence option
<F10> Launches the utility partition (if installed) during system start-up


Give it a try and let us know how it works.
User avatar
retrofanatic
Oldbie
 
Posts: 799
Joined: 2014-1-05 @ 03:56

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-14 @ 03:24

Wow, that's very cool. Thanks for the tip. That's why Vogons is so great. I'll load Jazz and Gods (two problem games) later and report back. Is there a good DOS program that can report system speed?
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-14 @ 03:35

Mau1wurf1977 wrote:Define "DOS Games" :)

For early DOS games I would rather go with a Pentium.


Yeah, kind of broad I know. I was thinking about later DOS games after 1992 or so that followed Wolf 3D. I'd rather use a 486DX2-66 or early Pentium too, but I want to know if any popular games from this era had speed issues or (as suggested by someone earlier) if a PII might even be better for games like Blood, Duke 3D, System Shock, etc.
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-14 @ 07:01

retrofanatic wrote:You may be in luck because the GX1 has a special key combination that slows the CPU speed (or maybe disables cache) on the fly. <Ctrl><Alt><\> or <Ctrl><Alt><#> (See below).


It works! Well, kind of. The slowdown is quite dramatic. I would guess that the processor is getting slowed down to a 386 level or maybe even lower. Jazz and Tyrian are too slow to play. However, you can do the key combo DURING the game and speed it back up to normal. Even Gods, which is very speed sensitive, seems to play okay.

The key combo makes a low-pitched speaker sound when you do it once, then a high-pitched sound (normal speed) when you do it again. It's like the old "Turbo" switch on a 286!
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby Mau1wurf1977 » 2014-6-14 @ 07:04

An old video of mine but explains my views / findings on using newer hardware for DOS gaming :)

https://www.youtube.com/watch?v=gzxnB2CD6aw
User avatar
Mau1wurf1977
l33t++
 
Posts: 7652
Joined: 2010-8-27 @ 04:15
Location: Western Australia

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby chinny22 » 2014-6-14 @ 12:59

I had more problems with our 486/66 playing older games when we fist got it. Next upgrade we got was a P2 400 and never ran into any games that I played on the 486 that wouldn't play on the P2. IMHO slot 1 PCs are great for late dos games and can even do early Win9x games as a bonus
User avatar
chinny22
Oldbie
 
Posts: 1885
Joined: 2011-8-26 @ 12:02
Location: Australian but living in the UK for now

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby archsan » 2014-6-14 @ 18:00

boxpressed wrote:
retrofanatic wrote:You may be in luck because the GX1 has a special key combination that slows the CPU speed (or maybe disables cache) on the fly. <Ctrl><Alt><\> or <Ctrl><Alt><#> (See below).


It works! Well, kind of. The slowdown is quite dramatic. I would guess that the processor is getting slowed down to a 386 level or maybe even lower. Jazz and Tyrian are too slow to play. However, you can do the key combo DURING the game and speed it back up to normal. Even Gods, which is very speed sensitive, seems to play okay.

The key combo makes a low-pitched speaker sound when you do it once, then a high-pitched sound (normal speed) when you do it again. It's like the old "Turbo" switch on a 286!


That's nice to know! GX1 comes with a riser board, right? How many ISA slots are there in your model?
"Any sufficiently advanced technology is indistinguishable from magic."—Arthur C. Clarke
"No way. Installing the drivers on these things always gives me a headache."—Guybrush Threepwood (on cutting-edge voodoo technology)
User avatar
archsan
Oldbie
 
Posts: 985
Joined: 2009-6-28 @ 15:30

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-14 @ 18:35

Yes, it comes with a riser board. There are 3 ISA slots and 3 PCI slots, although one slot is shared, I think. I think it is just enough:

SB Pro
GUS
Voodoo 2 SLI
S3 Virge PCI
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby AlphaWing » 2014-6-14 @ 19:44

That is interesting.
With the hidden slow down from keyboard toggle, an actual good thing to come from a OEM machine.
Thats rare!
User avatar
AlphaWing
Oldbie
 
Posts: 703
Joined: 2014-6-02 @ 15:34
Location: USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby retrofanatic » 2014-6-14 @ 23:12

Glad to help :happy: . I think that key combo works on other OEM dell machines as well. I also have a couple NEC pentium 1 machines that have a similar option as well.

It's especially great that the key combo works 'on the fly' during gameplay.

Can I ask you...did you use [control alt \] or [control alt #]?
User avatar
retrofanatic
Oldbie
 
Posts: 799
Joined: 2014-1-05 @ 03:56

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-14 @ 23:37

Ctrl Alt /

However, my vmm32.vxd just got borked upon bootup today. Don't think it is related, but I'll have to reinstall before I can do more testing.
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby archsan » 2014-6-15 @ 01:27

boxpressed wrote:Yes, it comes with a riser board. There are 3 ISA slots and 3 PCI slots, although one slot is shared, I think. I think it is just enough:

SB Pro
GUS
Voodoo 2 SLI
S3 Virge PCI



Yep, 3 slots are good (didn't notice you already said that in the first post). That would be two ISA soundcards + Roland MPU-IPC-T for me, just because I have a couple around. Thing is, getting a good copy of good BX mobos with 3 ISA slots such as ASUS P2B is becoming harder/more expensive today. So an OEM like Dell GX1 looks like a good alternative.

So if it's too slow for Tyrian... could it be running at 286 or at least 386/25 speed?
"Any sufficiently advanced technology is indistinguishable from magic."—Arthur C. Clarke
"No way. Installing the drivers on these things always gives me a headache."—Guybrush Threepwood (on cutting-edge voodoo technology)
User avatar
archsan
Oldbie
 
Posts: 985
Joined: 2009-6-28 @ 15:30

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-15 @ 01:38

I think that the Optiplex wasn't playing well with the IDE-to-CF adapter + Hitachi Microdrive, hence the corrupted vmm32.vxd. Right now I'm reinstalling Win98SE on the original 6GB drive (turned out not to be fried after all -- the floppy drive was). Once I'm up and running, I'm going to load Topbench to see how fast both modes run.

Also, I was reading my 14th edition of Mueller's Upgrading and Repairing PCs, and Mueller mentions that the Dell computers from this era use a proprietary ATX power supply. The connector fits all ATX boards, but the pins are rearranged. This means that it can kill other motherboards, and you can kill the Dell motherboard with standard ATX power supplies. Keep this in mind in case you pick up an Optiplex.
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby boxpressed » 2014-6-15 @ 02:21

OK, I ran Topbench for the first time. Pretty cool program. Here are the results:

Normal Mode: 337 (P2-333 /66 MHz FSB)
"Compatibility" Mode: 38 (Comparable to a 286-16)

I'm pretty happy with that. That opens up a whole range of mid-1980s games.
User avatar
boxpressed
Oldbie
 
Posts: 1069
Joined: 2014-5-20 @ 18:29
Location: Wisconsin, USA

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby retrofanatic » 2014-6-15 @ 04:38

boxpressed wrote:OK, I ran Topbench for the first time. Pretty cool program. Here are the results:

Normal Mode: 337 (P2-333 /66 MHz FSB)
"Compatibility" Mode: 38 (Comparable to a 286-16)

I'm pretty happy with that. That opens up a whole range of mid-1980s games.


Good job getting it back up and running.

That's great! Very good to know.

I didn't expect it to go that slow, but I guess that's good for really old games.
User avatar
retrofanatic
Oldbie
 
Posts: 799
Joined: 2014-1-05 @ 03:56

Re: Is a Pentium II Too Fast for a DOS Rig?

Postby Mau1wurf1977 » 2014-6-15 @ 04:52

I found that a typical Slot 1 system with Cache disabled performs on the level of a 386SX. The higher the FSB, faster the memory, tighter the timings, higher the CPU clock (e.g. 1.4 GHz Tualatin) this improves somewhat.

I found that even playing old games like Indiana Jones and The Last Crusade is pushing your patience on a Cache disabled Slot 1 machine. The loading times are quite slow and it wasn't much fun.
User avatar
Mau1wurf1977
l33t++
 
Posts: 7652
Joined: 2010-8-27 @ 04:15
Location: Western Australia

Next

Return to General Old Hardware

Who is online

Users browsing this forum: KCompRoom2000, knowledge [bot], luckybob, modbus, sirlemonhead, skitters, Thermalwrong, WileECoyote and 11 guests