What games are you intending to play? That Savage4 would struggle with Quake2 or Unreal. A voodoo3 would probably be a better bet, and more compatible with earlier 3D games.

I'm mostly trying to play DOS and 2D Windows games, though this thing's secondary function is for games like you mentioned. Wouldn't a Voodoo 3 be bottlenecked by the K6-2?

No they would be reasonably matched. And the V3 is excellent for DOS games.

athlon_p0wer wrote on 2021-10-05, 20:01:

I'm mostly trying to play DOS and 2D Windows games, though this thing's secondary function is for games like you mentioned. Wouldn't a Voodoo 3 be bottlenecked by the K6-2?

Yes it would be bottlenecked by a k6-2 but it is still a decent choice as the k6-2 is somewhat slow and the 3dfx drivers are optimized for them, so it keeps the driver overhead low.
A TNT2 MIGHT be bottlenecked by a K6-2 but it is actually a good match with that chip provided you use a early enough driver version.

A PIII at any speed is by and large faster clock per clock than any K6-2. It is faster than a k6-2/3+ in most cases for that matter.

M570... that board has a CMI-8330 onboard, which offers full SB16 compatibility that the YMF71x doesn't. I'd use both in parallel, with the YMF doing OPL3, SBPro2 and MIDI on A220I5 D1 P330, and the 8330 doing SB16 on A240 I7/3 (depending on whether you need LPT1 or COM2 more) D3.

Apart from that you can increase the bus speed on this board to 95MHz. That's probably overdoing it, but your K6-2 400 will probably also run at 5x83MHz. 15MHz faster core won't make much difference, but faster cache and RAM will. Possibly 4.5x95MHz will also work (427.5MHz), with the RAM and cache improvement far more relevant that the 12.5MHz faster core.

All the 400s I had did 450 easily. However, I didn't have a "super" 7 back in the day so can't say how much they didn't want to do 500 or how much I was fighting PCI problems with 83/2. Even 380s would do 450. 350s, now all the ones of those I had were not CXT, and they got stuck around the 366-375 mark, with the rare one struggling to 400, but probably needing 2.5V and more sink.

I don't want to overclock the FSB because the system gets a bit unstable at that point, so that isn't what I'm thinking for performance.

I got a laptop with a K6-2+ 550MHz which I'll put in there when I get my hands on some thermal paste. I already have the K6-2+ BIOS update installed and know to turn the voltage down to 2.0v, so that 128KB L2 cache should really boost it, even with the CPU still being at 400MHz.

Unfortunately, I can't use the sound chip on board because it requires a PCI bracket that came with the motherboard that I don't have.

I have almost the same board, M590. The FSB 100MHz is not stable, but 83MHz yes. I have a K6-2 300@380 at 83x4.5 and it's faster than @400 at 66x6. The downside is that according to Sandra, the FSB/PCI is synchronous, so 41MHz instead of 33, but the HDD controller manage it and the cards too (V3 2000 PCI). Not bad for a PCChips brand.

My system won't even do 75 before it gives up and starts crashing. I've made sure RAM and CPU settings are correct and tried different kinds of video/PCI cards, and even different CPUs. It's either buggy and unstable or just flat out forces me to reset the BIOS when I switch it to anything higher than 66MHz.

I have a PC Chips M571 and it only officially supports 75mhz FSB.
I can jumper it to 83mhz but it is essentially overclocking the chipset.
It does however work fine with my K6-3+ as long as I provide a fan blowing at the VRMs.
I have the same problem as althon_power in that I can't use the onboard audio without the stupid proprietary bracket.

I use mine with a Vortex 1 PCI, I did have a ISA ESS Audiodrive 1868 but I never could get it to cooperate with the Vortex or the Turtle Beach card I used to have in there. finally settled on the PCI only solution.
I do have a few other ISA cards lying around that I might try in there instead.

To the OP, if you are having stability issues play with the bios settings/RAM timings as well as different RAM sticks. My board is SUPER picky on what RAM it likes, some won't post at all, others are just slow as balls for no real reason.

Also what BIOS are you using?

Ydee wrote on 2021-10-06, 17:06:

I have almost the same board, M590. The FSB 100MHz is not stable, but 83MHz yes. I have a K6-2 300@380 at 83x4.5 and it's faster than @400 at 66x6. The downside is that according to Sandra, the FSB/PCI is synchronous, so 41MHz instead of 33, but the HDD controller manage it and the cards too (V3 2000 PCI). Not bad for a PCChips brand.

There should be a jumper for this. I can't remember which one it is on my board but it was within the CPU multiplier block.

It took me awhile to locate it (my fault it was clearly stated on the site that I was referencing) but once I did locate it fixed a lot of my stability issues.

BitWrangler wrote on 2021-10-06, 02:37:

All the 400s I had did 450 easily. However, I didn't have a "super" 7 back in the day so can't say how much they didn't want to do 500 or how much I was fighting PCI problems with 83/2. Even 380s would do 450. 350s, now all the ones of those I had were not CXT, and they got stuck around the 366-375 mark, with the rare one struggling to 400, but probably needing 2.5V and more sink.

Yeah pretty much my experience as well.

I have 3 350's and only one of them will hit 400, but it isn't really stable at that speed. The others won't even post past the 366-375 mark.

I'm using a slightly modded BIOS for K6-2+ support, which I'll be able to take advantage of once I get some thermal paste, but otherwise it's the last BIOS revision for this board.

I got it working at 75MHz. At 83MHz the system gives a video beep code, so the S3 can't handle anything higher than 75MHz. The AGP is locked in sync with my FSB speed, so I can't do anything about that part.

I had to go up to 2.3v from 2.2v, but 450MHz works. My fast RAM timings also run well too, so I got a few extra FPS in all my games (I'm testing with mainly GLQuake and Quake 2).

[EDIT]

Had to go to 2.5v to keep the 450MHz overstock, but it seems to be working well now.

Sounds like you have it pretty tightly tuned.
And Yeah can't really do anything about the AGP speed. I had somehow gotten it in my head that you were using a PCI card and I was thinking about the divider there.
75mhz is a sold FSB for a socket 7 rig anyway. You won't really be losing much performance.
That K6-2+ should give you a nice boost though when you get it up and going.

Once I get that in there I can run it at 450MHz stock voltage because it's actually an underclock from the 550MHz it can do.

I'm hoping this 2.5v thing doesn't cause any damage to the motherboard VRM while I use it. All the got is the CPU fan to cool them (it's a S370 cooler though, so it's pretty big for S7, and I'm thinking the fan might be just enough there to put some airflow over them).

athlon_p0wer wrote on 2021-10-07, 14:42:

Once I get that in there I can run it at 450MHz stock voltage because it's actually an underclock from the 550MHz it can do.

I'm hoping this 2.5v thing doesn't cause any damage to the motherboard VRM while I use it. All the got is the CPU fan to cool them (it's a S370 cooler though, so it's pretty big for S7, and I'm thinking the fan might be just enough there to put some airflow over them).

You should be fine, but you might need to direct a secondary fan directly at the VRMs. On my PC Chips board I had to run the chip at 2.2v which got the VRMS pretty toasty.
I actually used a smallish Socket A cooler with a brass plate, small for Socket A but rather large for Socket 7. This keeps the CPU nice and cool but the VRMs still got too warm.
I used a 80mm fan and just directed it directly at the VRMs. This did the trick to keep things nice and cool, and it isn't really loud with the case on.

Jasin Natael wrote on 2021-10-06, 19:59:

Ydee wrote on 2021-10-06, 17:06:

I have almost the same board, M590. The FSB 100MHz is not stable, but 83MHz yes. I have a K6-2 300@380 at 83x4.5 and it's faster than @400 at 66x6. The downside is that according to Sandra, the FSB/PCI is synchronous, so 41MHz instead of 33, but the HDD controller manage it and the cards too (V3 2000 PCI). Not bad for a PCChips brand.

There should be a jumper for this. I can't remember which one it is on my board but it was within the CPU multiplier block.

It took me awhile to locate it (my fault it was clearly stated on the site that I was referencing) but once I did locate it fixed a lot of my stability issues.

There is a jumperless BIOS on the M590, everything is set automatically via setup. But there are some undocumented jumpers on the board, unfortunately I don't know what function they have. SiS 5591/5595 should be capable of asynchronous FSB/PCI.

athlon_p0wer wrote on 2021-10-05, 19:38:

I have greatly extended the specs on my K6-2 build, and was wondering how much of it made sense and how much didn't. Also, I was curious if anybody could spot any bottlenecks in this system because there's one somewhere. I suspect it is the K6-2 itself or the video card, but it may be something else. I know the S3 Savage4 isn't that fast but I'm low on AGP cards and the only other one is a TNT2 which was bottlenecked by even a Pentium III so I know for a fact that it would be wasted in this system.

If you're squeamish about overclocking (I know I was/am) check out the write allocation and/or write combining tweaks in this post. I only recently discovered I was leaving free performance on the table. It turned out the benchmark results in 3D-performance got a bigger boost from applying the tweaks, than they did from the overlock I did to go from 400->450 MHz.

edit. I'm not sure how much of the above is applicable when you're using an AGP graphics card.