Socket 7 update!

I keep flip flopping between builds so I might start posts with such a heading going forwards

Yesterday the new CPU finally arrived so it was time to give it a try. Can I hit 600MHz??

Things didn’t start well. I set the motherboard voltage to 2V (as low as it goes) and swapped the CPU over. It’s rated for 1.6V but I know 2V is ok on these as some models are 2V such as the k6-2+ 570)

Power on. No POST

Crap. Did I buy a dead CPU?

It was still set at 4.5 x 100. So I tried turning things down

I got it to post at 4 x 100 after going down to 233MHz and going up slowly. But it would not go over 4 x 100

Something not right. I checked the voltage at the CPU and it turns out it’s only getting 1.25V at the 2V setting.

Managed to find a datasheet online for the voltage regulator which confirms that the motherboard manual is wrong. There is no 2V setting.

https://www.ardent-tool.com/datasheets/Cherry_CS5151.pdf

Im going to have to try it at 2.1V (actually 2.15V) a bit higher than I would have preferred!!

I was still having problems. Finally fixed with a new jumper. The original one must’ve been a bit loose across the pins and without the jumper, it outputs 1.25v instead of 2.15v

At least I have the option to make it a low power system after I’m done playing around! Also - going back several pages - I was playing around with o/cing the original Pentium 233MMX - but it wasn’t stable at 83 x 3.5 and needed more voltage. I now know I can go up a bit more in volts with it. The motherboard manual doesn’t have any mention of voltages between 2.9v and 3.3v but they are there in the datasheet

Now working at 2.15v. Time to try 6 x 100

Socket 7 post!

589? Damn. I wish it would round up!! 😅

Socket 7 - Updated my benchmark table for the socket 7 showing the progression of the upgrades

These are all done with the Voodoo3 2000 PCI I have (143MHz, SD-RAM variant)

Pretty pleased with the outcome! We have come a long way from the start. Pretty much 2x performance across the board, and up to 4x in some cases. Running stuff at higher resolutions in DOS with smooth frame rates is a first for a computer of mine. It's the first time I've had the right cpu/gpu & driver combo for it I think.

Mixed feelings now about what is next - I am kinda done tinkering with it as there is nothing else left to improve - yesterday I was just playing Quake 2 on it all afternoon, at ~600MHz, and had no crashes!

I'm curious how it would do in the K6 aiming for the stars thread. But with only having PCI, I'm limited to GF2 MX / GF4 MX or early ATI cards.

I always wondered why ancient chipsets could overclock to 83mhz
( or 80mhz for socket 4)
But the tx with low vio support couldn’t crack 83mhz.

You would have figured one of the overclock friendly board makes who kept selling tx boards into 1998 would have snuck in unofficial super 7 overclocking bus speeds with a patch for the HD ROM bug from the factory.

Now I wonder, none of my boards ever had unofficial and useful bus speeds (at least not socket 7)