I can confirm this problem (in stock v14, can't test svn at the moment). Definitely a bummer, would love to see this fixed for the v15 release! To shed further light on how to reproduce this: only Pentium-class machines are affected. To reproduce, create a setup with any Pentium-class board (I've te...

FYI, I've been using PCem on an Ivy Bridge-era laptop for years, with pretty good results. I can maintain near-100% emulation for anything up to a Pentium-133 or so, though it does of course depend heavily on what the emulated system is doing. My laptop's CPU is an i7-3632QM, base speed 2.2GHz and t...

From what I understand, v15 is supposed to have a totally redone recompiler, which is hardly "bugfixes"! I'm not privy to any inside information about what will be in it, but I have a feeling a lot of people will be pleasantly surprised.

Seconding leilei. It's an incredibly inefficient use of valuable time to have Sarah (or anyone else who's very deep in the PCem codebase) attending to requests that actually don't require much special expertise to carry out. The ATI Graphics Ultra Pro request is maybe not the best example (I'm not s...

PCem's CPU emulation is powered by an interpreter ( https://en.wikipedia.org/wiki/Interpreter_(computing) ) and a dynarec ( https://en.wikipedia.org/wiki/Dynamic_recompilation ). The pre-486-class systems use the interpreter, the Pentium-class systems use the dynarec, and the 486-class systems allow...

endeavor/1006cb0_.bi0 and revenge/1009af2_.bi0 are absolutely included in the code, in mem.c, and always have been. I'd suggest double-checking that again; hopefully you didn't remove any references to those, as they are entirely necessary to the basic functionality of the Endeavor and Revenge. pc15...

I can confirm that the Windows 8.1 patches for Spectre/Meltdown have had no noticeable impact on PCem performance on my Ivy Bridge-based system.

Hey, thanks for doing that testing. I can confirm your observations about the second way to trigger the bug. Just to clarify for all reading this: as you'll notice from the reports above, the fullscreen toggle trigger that I reported in the OP does occur when Video -> Resolution is set to "Cust...

Can anyone reproduce this? It should only take a moment to check. Not the end of the world, but it can get unwieldy as the window just grows and grows when there's a need to toggle back and forth several times between windowed and fullscreen. It would be helpful to know if this is specific to my set...

That's good to know. It'd be a nice addition, understandable that it wouldn't be a priority of course. Maybe someday...

Bit-accurate x87 emulation requires 80-bit floating point operations, as that's what x87 uses internally. If the host CPU's FPU was used to do this, this will destroy any chance of porting PCem to any architecture other than x86, because all other modern architectures support 64-bit as a maximum. T...

It's not just about accuracy/authenticity (though IMO that's reason enough to care about this). I definitely have run into various early-80s era software that throws unexpected behavior in PCem under certain circumstances which appears to be due to the lack of expected HDD access delays. Can't remem...

Just a shot in the dark, but could this be related to the bug I reported at viewtopic.php?f=2&t=2963?

This would be an excellent addition for sure.

Just a minor but annoying bug, probably quite easy to track down and would be nice to get it stamped out for v14. Steps to reproduce: - Set Video > Resolution to anything other than "Original". - Set Video > Remember Size & Position. - Set Video > Output stretch-mode to anything other ...

Awesome idea, thanks for adding this! I see that 56x is missing from the list of available speeds--any particular reason for that? I realize that the accuracy is iffy toward the higher end of the speed range in this implementation, but just about every other common speed now seems to be accounted fo...

If someone is going to go to the trouble of adding an EMS board to PCem, I'd much rather see a period-accurate one emulated than some recent hobbyist board. Is there anything about the Lo-tech that makes it particularly desirable?

Just a quick patch to fix a missing tooltip in the Configuration Manager window. Not a big deal, but I'm sure I'm not the only one who relies on tooltips and has some anxiety about clicking "mystery meat" buttons...

Hmm, that's unfortunate. Thanks for looking into it, Sarah. I know we've got some wxWidgets gurus here, hopefully someone has a clue what can be done about this under Windows... anyone?

aladd10, as the name suggests, was the BIOS for the Gateway OEM ALi Aladdin motherboard, not the Zappa. The Gateway OEM Zappa is called zappb11. It may just be identical to the standard Advanced/ZP though, with Gateway logos and such added but otherwise no change in features or functionality, in whi...

Sorry if this has been discussed before, but have there ever been any attempts to look into trapping ALT+TAB? As things stand, it's getting sent to both the guest and the host, in fullscreen as well as windowed mode. This, of course, makes it basically impossible to use ALT+TAB on the emulated syste...

Looks good! Love your shader setup too--what package/settings is that?

Loving this, and the recent PB570/CL emulation as well, thank you!

Can't speak to whether it's a great use of your Sunday, but this is excellent stuff! I've been super interested for a long time in knowing how these comparisons would shake out, it's nice to have some hard data.

Funny that this should come up now, I was actually just thinking recently about how nice it would be to have Trio64V+ and Vibra16 emulation in PCem, not specifically the integrated Advanced/EV versions but just generally speaking. I had a couple of standalone Trio64V+ and Vibra16 cards back in the d...

What renderer are you using (Settings->Render driver)? That's the only thing that is likely to cause a performance regression - for just about everyone else v13.x is faster than v12... I haven't been having any of szadycbr's issues but this is good to know, thanks. I usually just leave the render d...

No problem at all, I'll hold off on digging further into this until the recompiler rework is done. (Just as a point of order, the observation I was trying to make was that the Win9x shutdown screen does not have anything even close to the same performance behavior as the DOS prompt idle loop, which ...

Just noticed another major recompiler choker: the "it's now safe to turn off your computer" screen after shutting down Win9x. The level of slowdown is exactly the same as the "no boot device" idle loop I mentioned above, suggesting that they may both be caused by the same recompi...

Not sure if it's related at all, but I've noticed that the BIOSes of all machines behave exactly this way (completely failing to see that any HDD is installed at all) if the HDD image file is read-only. I ran into that once and was tearing my hair out for a while until I figured it out. PCem should ...

Finally getting a chance to play around with PCem 13.1, and sure enough, it looks like some of those recent dynarec tweaks have MASSIVELY improved execution rates at the DOS prompt, game menus, and other idle-loop areas that previously brought the emulator to its knees. These loops do still cause no...