https://theretroweb.com/motherboards/?showIma … 1&name=ATC-5200

Choose your version.
Yes, looks like it is possible.

hi friend, mine is v1

brunofbrsilva wrote on 2023-07-06, 16:40:

hi friend, mine is v1

Download and flash the latest BIOS.

Follow the instructions relative to the K6-2 cpu.

Should be all that's needed. Maybe you don't even have tu update the BIOS.
Let us know.

The processor I have is the k6-2+ 550 on the site that the friend sent me I found the file "AMD K6-2/3 Additional Settings", it contains the frequency configuration of the k6-2+ 450 and the k6-2 550 which of the two configurations I better follow?

brunofbrsilva wrote on 2023-07-06, 17:12:

The processor I have is the k6-2+ 550 on the site that the friend sent me I found the file "AMD K6-2/3 Additional Settings", it contains the frequency configuration of the k6-2+ 450 and the k6-2 550 which of the two configurations I better follow?

Post a pic of the cpu that you have.

Your cpu seems to be 2.0 Vcore. As per manual, lowest Vcore configurable is 2.2V.
Unless someone has anything to add, your cpu should work but with a slight overvolt of 0.2V

Cpu settings are those of the manual, follow 100MHz and 5.5x multiplier.

follow the image of my processor

Confirming That cpu should be fine at 2.2v setting.

It should also have a good chance at running at 600mhz, 6x (2x setting on mobo)

The cpu is probably moddable to 3+ btw, but I advise against doing that to a 550 2+ as it is kind of a rare cpu.

It is better to do it to a 570 2+

thank you very much for your help friend, the processor will arrive tomorrow and as soon as i have it with me i will carry out the tests.

brunofbrsilva wrote on 2023-07-07, 02:27:

thank you very much for your help friend, the processor will arrive tomorrow and as soon as i have it with me i will carry out the tests.

Can’t wait to hear how it goes! 😀

Good morning friends, a stupid question, is there any way to reduce this 0.1v in a physical way? Any changes to the components on the motherboard?
I heard that if you turn off all the jumpers the vcore voltage will be 2.0 on some motherboards, is that correct?

Many variable voltage regulator ICs are set by reference resistors, and the jumpers switch in various resistors to give the various voltages. So depending on the particular regulator IC and the combinations of resistors installed, then combinations of jumpers, putting resistors in parallel may give undocumented voltage settings. You can pull the datasheet for the IC, read the resistor values off the board and work it out exactly, or you can just try stuff out and measure what you get.

When implemented in this way, there's usually what you might call a master resistance that all the other resistors add to, physically changing that for a low or higher resistance may shift all your settings up or down. But you'll have to figure out all of the settings from scratch the table in the manual will now be wrong. For instance if your highest setting is 3.2V and lowest 2.5, then you might be able to use a resistance that makes highest now 2.7 and lowest 2.0.

This is for socket 7 regulator implementations, some may apply to socket 5 and late 486 boards, some earlier slot 1 boards, but then they can get fancier voltage regulators where it's all built in and you are setting the voltage to preset values with a bit code logic on:off rather than external analog values.

I understood perfectly friend, great explanation, and to perform the test I should measure the resulting voltage directly on the socket pin?

brunofbrsilva wrote on 2023-07-07, 14:33:

I understood perfectly friend, great explanation, and to perform the test I should measure the resulting voltage directly on the socket pin?

Yes. You can do that without the cpu installed.

I understood perfectly, the most interesting thing is that in the manual there is a line that says "Supports CPU core voltage range from 2.0V up to 3.5V." although the 2.0 voltage is not available in the configuration screen.

brunofbrsilva wrote on 2023-07-07, 14:47:

I understood perfectly, the most interesting thing is that in the manual there is a line that says "Supports CPU core voltage range from 2.0V up to 3.5V." although the 2.0 voltage is not available in the configuration screen.

Try settings, Bitwrangler is correct when he states that boards may not report all that is possible.
Funny experiment! 😀

Perfect, tonight the processor arrives and I can start the tests, as soon as possible, I'll come back with the results

About the BIOS on your ATC-5200 v1, yes you need the latest Ver. 1.0 08 (01/26/2000) BIOS for your K6-2+/550. This Ver. 1.0 08 BIOS fully supports the K6-2+ and K6-III+ CPU and also has IDE HDD support up to 128GiB. 😀
All earlier BIOS versions do not support your K6-2+ and are limited to 32GB Harddisks.

If your ATC-5200 has an older BIOS, it is best to flash the latest 1.0 08 BIOS before you install the K6-2+. You can use any regular K6-2 or Pentium CPU for that.
But be careful to set the SW2 dipswitches back to the 2.0V or 2.1V setting you found from your experiment, before installing the K6-2+. 😉
Also take care to set JP1 for Dual Voltage mode.

I believe this ATC-5200 board has the fancier voltage regulator that BitWrangler talked about and the Vcore can be set from 2.0V to 3.5V in 0.1V steps, using all 16 combinations of the four SW2 dipswitches.
Can you tell us which voltage regulator IC is on your board? It should be the chip between the first ISA slot and the corner of the CPU socket.

Jan

hi friend, I don't have the motherboard right now, as soon as I get home I'll send you a photo of the regulator, I have a question now, as this processor (K6-2+ 550) is not in the manual which jp1 configuration should i follow?

manual: https://theretroweb.com/motherboard/manual/at … a4608911934.pdf
aditional settings: https://theretroweb.com/motherboard/manual/at … a4608911934.pdf