News Frustrated Retro Gamer Overclocks ISA Bus Over 200%

[Admin]

If retro gaming on original hardware isn’t as enjoyable as you remembered, try overclocking for some worthwhile gains.

Frustrated Retro Gamer Overclocks ISA Bus Over 200% : Read more

 

[ex_bubblehead]

Kids today, always thinking they've discovered something no one else has ever thought of. This was quite regularly done back in the day. Not news at all.

 

[bit_user]

Cool to do this "for science" but...

Moving up to an amazing ISA bus speed of 25 MHz, the system remained stable, and VswitchZero says the system could rival VESA Local Bus systems in benchmarks.

I didn't think there even were any 486DX2-66 that didn't have a VLB slot.

In between, another option was EISA. I had a friend with a 486DX-50 (at least I think it was DX, not DX2) and it had an EISA graphics card but not VLB. EISA was 2x the bandwidth of ISA, I think for being 32-bit instead of 16-bit.

 

[bit_user]

This was quite regularly done back in the day. Not news at all.

I had never heard of overclocking, back in the day, but someone later told me that you could overclock a 386 by similar (~2x) amounts! I wish I'd have known back then, but actually no way my dad would've let me risk frying his CPU.

 

[OriginFree]

I had never heard of overclocking, back in the day, but someone later told me that you could overclock a 386 by similar (~2x) amounts! I wish I'd have known back then, but actually no way my dad would've let me risk frying his CPU.

Yes this was definitely a thing all the way back to the 8086 / 8088 (not sure about earlier). We routinely overclocked our 286 / 386SX / DX to get that extra boost. Going from 12 MHz to 16 was a huge jump (33%+) and was routine in our circles. Especially once the hardware was "outdated" and they were given to us to scrap once the new hardware came in. It's much more fun to play with a machine that you don't have to pay to replace if things go sideways.

Then we got drop in replacements (which I know date back to at least the 8088/8086 days), clock "doubled" chips and eventually chips that overclocked themselves.

I have to admit I do miss spending the week tweaking a system & the boot files just to be able to get the newest software to run on the weekend. Then again I may have blocked out all the bad parts 30+ years on.

 

[vern72]

I didn't think there even were any 486DX2-66 that didn't have a VLB slot.

When I got my first PC (a 486DX/20), I insisted that it have PCI slots. I never had VL-Bus in any of my systems.

 

[bit_user]

When I got my first PC (a 486DX/20), I insisted that it have PCI slots. I never had VL-Bus in any of my systems.

That's interesting. I never heard of a 486DX/20. 486SX/20, sure.

PCI didn't come along until the Pentium, which means older, lower-speed 486's were all ISA, EISA, or VLB. I never heard anything bad about VLB. Given the choice, I'd definitely go with PCI, though.

I had an AMD 486DX3-120, IIRC. And it had PCI slots. Weirdly, it ran PCI at 40 MHz, which was out-of-spec.

 

[Amdlova]

I have a little time with a 486 dx... I don't remember if I make some oc via jumper... jumped after for a pentium and make some overclock... man the math with the jumpers good times. Today you enter in bios do some increments and it's done.

 

[Stesmi]

That's interesting. I never heard of a 486DX/20. 486SX/20, sure.

PCI didn't come along until the Pentium, which means older, lower-speed 486's were all ISA, EISA, or VLB. I never heard anything bad about VLB. Given the choice, I'd definitely go with PCI, though.

I had an AMD 486DX3-120, IIRC. And it had PCI slots. Weirdly, it ran PCI at 40 MHz, which was out-of-spec.

I don't recall a 486DX-20, either. Doesn't mean one didn't exist, DX-25, yes.

Remember that early in the Pentium era, when they were hard to get hold of and got recalled, etc, there were some 486 PCI motherboards out there to cate for the Ooh Ahh new bus (PCI), but affordable/can get hold of. I know I saw one. Wasn't there a MicroStar motherboard with PCI back in like 1995, and something like a Pine Technology or something?

Found one, but I don't know when it's from.

https://theretroweb.com/motherboard/manual/pt-431a-man-60673d25230cd160845313.pdf

 

[Stesmi]

Kids today, always thinking they've discovered something no one else has ever thought of. This was quite regularly done back in the day. Not news at all.

Very many ISA cards that had trouble going up in bus speed. Personally I never heard of anyone going as high as 25MHz. What cards did you regularly run at 25MHz or above?

 

[jonfitch]

486s really were pushed to the limit to try to run the original Doom engine. You really needed a Pentium 75 at the minimum, if not a Pentium 100 MHz to run without any hitches.

 

[bit_user]

486s really were pushed to the limit to try to run the original Doom engine. You really needed a Pentium 75 at the minimum, if not a Pentium 100 MHz to run without any hitches.

I'm pretty sure you're thinking of Quake.

I played all the way through the original Doom on a 386SX/20 ...I could be off on the clock speed. Yeah, I had to shrink the viewport down a few sizes, to get playable framerates. On a 486DX/33, I'm pretty sure it would play smoothly at the full 320x240 resolution.

Quake definitely demanded a Pentium. I first played it on a Pentium 75, and it was definitely playable. When I got a hold of a Pentium Pro 200, I remember that machine was a real beast.

 

[AncientNordicRoots]

I really enjoyed watching this. I had an old 486 DX4, and never even dreamed of doing this. I just accepted crappy performance.

I wish I could have remembered when we got that old thing, I feel like it was in 94 or 95.

 

[Misgar]

My first overclock involved de-soldering the 3MHz HC6U crystal associated with a 65C02 processor and replacing it with a socket. I then tried various "faster" crystals until the system crashed. If memory serves me right, that would be in 1985, a year before I bought an 8086 computer. I upgraded that system with an NEC V30 CPU.

 

[jonfitch]

I'm pretty sure you're thinking of Quake.

I played all the way through the original Doom on a 386SX/20 ...I could be off on the clock speed. Yeah, I had to shrink the viewport down a few sizes, to get playable framerates. On a 486DX/33, I'm pretty sure it would play smoothly at the full 320x240 resolution.

Quake definitely demanded a Pentium. I first played it on a Pentium 75, and it was definitely playable. When I got a hold of a Pentium Pro 200, I remember that machine was a real beast.

Naw, I'm thinking of Doom 2 actually. I remember playing that at Costco in the 90s, they had a couple of PCs on display with the game installed. It was always stuttering on the 486 DX4s when there was a lot of action on the screen, but ran smoothly on the Pentium 100Mhz. They had them hooked up to 640x480 CRTs.