Yep I had to use the lowest cache timings with the 15ns cache I have in the C2. I tried 66x3 and was able to beat my previous score just a bit. Serpent was right about Doom preferring the faster bus speed. Really wanted to get Quake running but kept hitting malloc errors when launching, kinda similar to what happens when I try running this cpu at too high a voltage at 180. I bet if I could dial in the voltage between the 3-4v jumper setting I could get Quake running.

I’ve Probly asked before but where are you sourcing 10-12ns chips? Digi-key?

I bet this is going to bring a huge "NO!" but what about a Cyrix GXm or National Semiconductor Geode GXm CPU and accompanying motherboard?

They are basically higher clocked versions of the Cyrix 5x86. The newer ones also support MMX.

Use SDRAM, but only run the RAM at 33Mhz.
Bus speeds supported are only 30 and 33Mhz, but the CPU multiplier goes all the way down to 5x (possibly 4x if an interposer was made for a BGA version) and up to 10x.

Onboard video and sound.

Best motherboards came with 2x PCI and 2x ISA.

I wouldn't say "NO!" right away but wouldn't the GXm be considered a true 586 CPU rather than a 486?

cyclone3d wrote on 2021-11-24, 17:49:

I bet this is going to bring a huge "NO!" but what about a Cyrix GXm or National Semiconductor Geode GXm CPU and accompanying mo […]
Show full quote

I bet this is going to bring a huge "NO!" but what about a Cyrix GXm or National Semiconductor Geode GXm CPU and accompanying motherboard?

They are basically higher clocked versions of the Cyrix 5x86. The newer ones also support MMX.

Use SDRAM, but only run the RAM at 33Mhz.
Bus speeds supported are only 30 and 33Mhz, but the CPU multiplier goes all the way down to 5x (possibly 4x if an interposer was made for a BGA version) and up to 10x.

Onboard video and sound.

Best motherboards came with 2x PCI and 2x ISA.

One has to wonder why a media GX couldn’t be adapted to a standard 486 motherboard but disable the on chip accessories?

Probably because the interrupts and other lines that they are assumed sole user of aren't brought out to the edge of the chip.

appiah4 wrote on 2021-11-25, 07:46:

I wouldn't say "NO!" right away but wouldn't the GXm be considered a true 586 CPU rather than a 486?

I can't seem to find any specific info on whether or not the regular Pentium instructions were on any of the GX series. The regular GX and GXi sound like they are just faster 5x86 chips.

I guess an instruction test program will need to be run on them to find out for sure.

I do have a motherboard and a couple of the low voltages (2.5v) 233 GXm CPUs on the way so I can test once th y get here. The CPUs are coming from China so it may take a while. I might already have a GX or GXm chip somewhere though.

According to wiki, https://en.wikipedia.org/wiki/X86_instruction … ed_with_Pentium , the Pentium added CPUID, CMPXCHG8B, RDMSR, RDTSC, WRMSR, and RSM. These instructions do show up upon reviewing the GXm databook.

Ok, so maybe only the pre-GXm GX and GXi chips could be considered 486 class.

Is a Cyrix 5x86 really even 5th gen? It's more like 4.5th gen, so I guess the MediaGX would be too.

cyclone3d wrote on 2021-11-27, 08:10:

Ok, so maybe only the pre-GXm GX and GXi chips could be considered 486 class.

Perhaps. I do not have the original Cyrix MediaGX databook to check the instruction set.

But even if the GXm supports Pentium and MMX instructions, does that really count as Pentium class or 5th generation? It isn't superscalar.

Don't the Cyrix 486DLC and SLC CPUs, for example, support the 486 instruction set? Would you consider these 486-class CPUs? I don't. To me, the Cyrix 5x86 and MediaGx are more a 486 than a Pentium.

486DLC is most definitely a 486 CPU, regardless of socket. All 486 software run on it.

appiah4 wrote on 2021-11-28, 13:31:

486DLC is most definitely a 486 CPU, regardless of socket. All 486 software run on it.

+1

If we're including MediaGX then my Winchip is the fastest 486 😜 .... what? It's single pipe and in order execution, more 486 than pentium.

Yeah, Winchip C6 is more or less 486.

Maybe we should start another thread for post socket-3 486 like CPUs.... Or should we just decimate the socket 3 scores in this thread?

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor.
So it is about the fastest Socket 3 hardware really.
If a CPU fits Socket 3 without interposer - it should be considered.
Otherwise - probably not.

pshipkov wrote on 2021-11-28, 21:13:

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor. So it […]
Show full quote

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor.
So it is about the fastest Socket 3 hardware really.
If a CPU fits Socket 3 without interposer - it should be considered.
Otherwise - probably not.

I agree, this should be CPU that fits in Socket3 and works like 486, not 586 like Cyrix.
But we can start another battle with any 486 socket, like Winchip or mGX 😀

lukas12p wrote on 2021-11-28, 21:46:

pshipkov wrote on 2021-11-28, 21:13:

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor. So it […]
Show full quote

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor.
So it is about the fastest Socket 3 hardware really.
If a CPU fits Socket 3 without interposer - it should be considered.
Otherwise - probably not.

I agree, this should be CPU that fits in Socket3 and works like 486, not 586 like Cyrix.
But we can start another battle with any 486 socket, like Winchip or mGX 😀

Cyrix 5x86 is not really a 586 CPU, it is a 486 CPU with some extra functions but not the complete 586 command set. 486 is the only architecture it can be said is 100% compatible with. 6x86 was Cyrix's 586 CPU here. I think the 5x86 easily qualifies as a 486 CPU.

Isn’t it possible to adapt a socket 3 chip to socket 5/7 socket?

appiah4 wrote on 2021-11-29, 05:13:

lukas12p wrote on 2021-11-28, 21:46:

pshipkov wrote on 2021-11-28, 21:13:

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor. So it […]
Show full quote

The name of the thread is a bit misleading since it says "world's fastest 486" but first post is about a hybrid processor.
So it is about the fastest Socket 3 hardware really.
If a CPU fits Socket 3 without interposer - it should be considered.
Otherwise - probably not.

I agree, this should be CPU that fits in Socket3 and works like 486, not 586 like Cyrix.
But we can start another battle with any 486 socket, like Winchip or mGX 😀

Cyrix 5x86 is not really a 586 CPU, it is a 486 CPU with some extra functions but not the complete 586 command set. 486 is the only architecture it can be said is 100% compatible with. 6x86 was Cyrix's 586 CPU here. I think the 5x86 easily qualifies as a 486 CPU.

I agree, cyrix 586 should count as a 486

Just like cyrix 686 should count at 586.

IMO, I would disregard anything where the supporting chipset is custom designed for the cpu or gives significant advantage (MediaGX, Vortex86SX, any of the socket 5 486class cpus) because it would get difficult to separate if performance is cpu based or due to improved memory/bus latencies.