One guess is you could have kept all your childhood viruses on there, kudos, not many people go for that level of authenticity. 🤣

BitWrangler wrote on Yesterday, 22:00:

One guess is you could have kept all your childhood viruses on there, kudos, not many people go for that level of authenticity. 🤣

Unfortunately, original HDD was wiped or swapped, so this is a modern install of WinXP. My main suspect is that OneCoreApi may have left something even after uninstallation. Probably I'll have to reinstall clean WinXP SP3 again, this time without OCA and LegacyUpdate updates.

Or might it be because of USB mouse (Microsoft wheel mouse optical) or some hidden IRQ conflict? Maybe the GPU is somehow too fast for this? There was an Ati Radeon 9600 128mb agp that I was blaming first, then I added RAM to 768mb, changed CPU from Willamente 1.8 to Northwood 2.0 (twice the cache), but upgrade improved almost nothing.

Caps around CPU VRM are just a little bulging and there are some neutralized (by me) corrosion from cat urine (not capacitor acid), but in theory this shouldn't affect performance untill it breaks afaik.

Combining a Pentium 4 with SDR SDRAM was never a good idea and was only done out of desperation. If it were me, I'd install Windows 2000 or XP SP1 to try and lighten the load the OS adds.

It definitely should be faster for Warcraft 3 with that CPU and that video card. My instinct makes me think there's an AGP speed issue from a misconfigured/absent chipset driver.

Unfortunately, original HDD was wiped or swapped, so this is a modern install of WinXP.
My main suspect is that OneCoreApi may have left something even after uninstallation.
Probably I'll have to reinstall clean WinXP SP3 again, this time without OCA and LegacyUpdate updates.

I've never had such issues with OneCoreAPI, though I also never used it on a Pentium IV.
Speaking of the Pentium IV, I had a Prescott once and it ran Windows XP SP2 very well at the time.
I remember that HyperThreading was enabled in CMOS Setup and that Task-Manager showed two CPUs.
I wonder if the Northwood can do HT, too, maybe it would help performance wise.

crapasanya wrote on Yesterday, 21:03:

and what are the chances of fixing it without reinstalling the OS?

In those cases the pretty obvious way is to do a second parallel installation, and dual boot with it

So you can compare them and you haven't to waste tons of your time reinstalling things each time.

If the problem persist on the fresh install it's a HW/BIOS problem

If the problem goes away, you have all the time to try to fix the old install, or keep the new one as the main.

Whatever the result a second install is obviously a life saver in case of serious problems on the first one.

Having a single install is just stupid, no matter if it works correctly or not, no matter if we are talking about DOS, XP or W10/11

I’ve heard that not updating the chipset drivers for NetBurst platforms can cause performance issues, but that was primarily in reference to Willamette and possibly pre-Windows XP (but I could be misremembering). Worth a shot, maybe?

I have some captures from a Northwood 2.4 GHz computer on my YT channel that might help you out, to get a reference for how a Northwood system should roughly perform. At least for games like Mafia, UT2003, Postal 2, Doom 3, Butcher Bay and Morrowind (etc.).