awesome, I'll try it on my <386 systems

Great news and I loved the "retro upgrade" idea!

Excellent, I've got a V20 to try this new version.

Hi guys, I want to buy a house so I'm selling the world's fastest V20, vintage RARE!!!1, as-is no returns.

@Chkcpu jokes aside, it is indeed a V20 (would be nice to distinguish between V20-V30) but clocked at 9,54 MHz as per the BIOS. The presence of the 8087 is correctly detected.

Seems to be working just fine for me, though I'm not sure why it wrote the same information to the report file 4 times. I only ran report.bat once.

Thank you ao much for your contributions to the retro community!

I have a 386 mobo I may be able to try this out on.

konc wrote on 2022-12-04, 19:40:

Hi guys, I want to buy a house so I'm selling the world's fastest V20, vintage RARE!!!1, as-is no returns. […]
Show full quote

Hi guys, I want to buy a house so I'm selling the world's fastest V20, vintage RARE!!!1, as-is no returns.

IMG_20221204_212557.jpg

@Chkcpu jokes aside, it is indeed a V20 (would be nice to distinguish between V20-V30) but clocked at 9,54 MHz as per the BIOS. The presence of the 8087 is correctly detected.
MYCPU.TXT

Whoa!! That is one fast V20! 😀
konc, thanks for the testrun on this special CPU. I clearly have to fix the speed measurement on these NEC models.
I'm presently using the same timing correction factor as for the 8086/8088, but the loop of divide instructions I use for speed determination is appearently executed much faster by the V20.

I will try to fix this in the next beta version.
Cheers, Jan

maxtherabbit wrote on 2022-12-04, 20:00:

Seems to be working just fine for me, though I'm not sure why it wrote the same information to the report file 4 times. I only ran report.bat once.

maxtherabbit, thanks for the 286 testrun!
I assume this 286 CPU is running at 20MHz, and has indeed a 80287 companion?

The REPORT.BAT file calls CHKCPU indeed 5 times, each time with a different command-line switch to get all possible outputs in the MYCPU.TXT file. Very useful on later 486 and Pentium class CPUs but most switches have no effect on 8086/8088-80286 CPUs, so the first 4 runs you see in the log are identical. But it is a good test to see if the speed measurement is stable. 😉

Jan

Chkcpu wrote on 2022-12-04, 22:22:

I assume this 286 CPU is running at 20MHz, and has indeed a 80287 companion?

yessir

Cool, looking forward to testing, I've got a 286 16MHz wo/FPU I'll try on tonight.

Yep works well here.

mwdmeyer wrote on 2022-12-05, 08:42:

Yep works well here.

Thanks, looks great. Although the speed reading is a tad high, just as in maxtherabbit's report.
This 4.5%-5% too high speed indication on 286 is a small deviation, but I like to have it more accurate and I will adjust for it in the next CHKCPU version.

Cheers, Jan

Hello, and thanks for updating your program, I will download it but at the moment I only have PCs from 386 up, my 286 has a broken power supply, I have to try to fix it but it takes time, and for the moment I work on motherboards more modern, let's say from socket 7 up.
I know your modified BIOSes, I use one on a QDI Titanium IB+ with a K6-3-400, I have installed other K6-2 400s on both VX and TX motherboards (with switching voltage regulators), although the BIOS doesn't recognizes correctly, however they work at 400Mhz, and in these cards I've already used your program, I'll try to try the latest version as soon as possible.

Thanks PC@LIVE, yes any CHKCPU report is welcome. 😀

About the really Vintage PCs, does any of you have a 8086/8088 system available to test CHKCPU on?
With the unusual high speed reading on konc's V20 CPU, I'm curios what the original 8086/8088 would show. 😉

Thanks, Jan

Chkcpu wrote on 2022-12-05, 22:00:

Thanks PC@LIVE, yes any CHKCPU report is welcome. :) […]
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Thanks PC@LIVE, yes any CHKCPU report is welcome. 😀

About the really Vintage PCs, does any of you have a 8086/8088 system available to test CHKCPU on?
With the unusual high speed reading on konc's V20 CPU, I'm curios what the original 8086/8088 would show. 😉

Thanks, Jan

Please don't worry, if I can download it there's no problem, I always use it on the PCs I repair, both old and more modern, in recent days I've used it in a P4 2.93 (775) with DDR2 RAM, I usually use (such as HD ) an IDE-CF adapter with an older DOS.
I tried to download your updated program a little while ago, from the link in the first message, but the card disappears and I can't save it, it could be a problem with my internet PC, but if you have time you can check if it works, thanks.
Unfortunately I don't have the motherboard and RAM chips to build a PC XT, I have a couple of CPUs, and video controller cards and pretty much everything needed to build one, I had an IBM PC years ago I think it was PS2-30, sadly a family member gave it as a gift

Hey Jan, how hard would it be to make it colorful like memtest86+

Chkcpu wrote on 2022-12-05, 22:00:

Thanks PC@LIVE, yes any CHKCPU report is welcome. :) […]
Show full quote

Thanks PC@LIVE, yes any CHKCPU report is welcome. 😀

About the really Vintage PCs, does any of you have a 8086/8088 system available to test CHKCPU on?
With the unusual high speed reading on konc's V20 CPU, I'm curios what the original 8086/8088 would show. 😉

Thanks, Jan

If none has one handy I'll put back the original 8088 that got replaced by the V20 and give it a run

PC@LIVE wrote on 2022-12-05, 22:19:

I tried to download your updated program a little while ago, from the link in the first message, but the card disappears and I can't save it, it could be a problem with my internet PC, but if you have time you can check if it works, thanks.

I just checked the download link in the first message, but it works fine here.
If you still can't download it, send me a PM or an e-mail and I will send you the file in return.

Jan

Some browsers block the download as unsafe, you need to manually save (eg. right click -> save link as) and accept saving the file. Chrome for example needs this.