What's the current cache configuration? You can use CACHECHK or Speedsys to find out if you're not 100% certain.

I'm asking because if for example you do have some cache now, say 128KB, and you intend to upgrade it to 512KB the performance increase might not be what you expect. Different story If currently there is no cache of course.

With cache bigger is not always better, it depends on how much main memory you've got installed.

https://dosdays.co.uk/topics/cache.php

That SX2 50 MHz could run at 66 MHz by moving J25 to the 2-3 position.

And like konc said, having or not having an L2 cache makes a world of difference. 128kB or 512kB not so much.

Not sure the OPTi 82C802 is VLB capable, the Cirrus Logic GD-5428 is. That's a plus for Doom. So hopefully that Cirrus Logic is hooked up to that bus, and not the ISA bus.

https://www.aliexpress.com/item/1005007322785936.html - these look like they would do for the main

Kekkula wrote on Yesterday, 08:28:

With cache bigger is not always better, it depends on how much main memory you've got installed.

https://dosdays.co.uk/topics/cache.php

It's like 99% of the time that larger size cache has better performance. No idea why would anyone assume otherwise.

It's not only memory cacheable area but also data retention. In perfect world crucial data would fit inside L1 cache. But if it's too large. It's still better to fit inside L2. Unless we have a 386 that doesn't have on-chip L1 at all.

Sometimes, depends on the chipset, the larger cache could mean more relaxed cache timings and any benefit of a larger cache would be voided. But thankfully this is not the case most of the time.

Which ever cache size 256/512KB lets you run the fastest timings... then I would upgrade the video card.

Warcraft 2 & Starcraft are directx compatible in windows and use BitBlt'ing. So a fast 2D card would speed it up.

As I had a PB450 based system (don't any more unfortunately), only ISA video cards (i.e., a downgrade) are possible in the stock configuration. The manual describes an unusual option, where by purchasing a different riser card and replacement BIOS, a PCI bus could be added after the fact (using an OPTi VLB-to-PCI bridge). Whether it's actually possible to still find that card or not, if you aren't satisfied with the onboard VLB CL-GD5428, I feel your efforts would be better placed in building a second system (like a Socket 7) for things that aren't fast enough on this one.

By the way, check out mpe's benchmark comparison chart: https://dependency-injection.com/wp-content/u … 01-1024x736.png
(and full article: https://dependency-injection.com/vlb-vga-group-test/)

Your onboard video is comparable to the SPEA V7 Vega on that chart.
As you can see, it's a budget chip and isn't the fastest, but is still not a slouch and a video upgrade isn't going to work any fps miracles.

Thanks for the replies

konc wrote on Yesterday, 07:02:

What's the current cache configuration? You can use CACHECHK or Speedsys to find out if you're not 100% certain.

I'll run this test this evening but at present I have no cache chips installed on the motherboard so I'm assuming that means 0. Looking up my CPU there is no built in L2 Cache.

PD2JK wrote on Yesterday, 09:28:

That SX2 50 MHz could run at 66 MHz by moving J25 to the 2-3 position.

This would be an easy performance gain but is this true? Not sure if I understand but it looks like there's two separate models of the 486SX2 - one for 50MHz vs 66MHz? Is there any harm in trying to move the jumper anyway and testing?

Matth79 wrote on Yesterday, 14:44:

https://www.aliexpress.com/item/1005007322785936.html - these look like they would do for the main

I'm assuming I would want to test any chips I get from Aliexpress right?

jakethompson1 wrote on Yesterday, 18:00:

By the way, check out mpe's benchmark comparison chart: https://dependency-injection.com/wp-content/u … 01-1024x736.png (and ful […]
Show full quote

By the way, check out mpe's benchmark comparison chart: https://dependency-injection.com/wp-content/u … 01-1024x736.png
(and full article: https://dependency-injection.com/vlb-vga-group-test/)

Your onboard video is comparable to the SPEA V7 Vega on that chart.
As you can see, it's a budget chip and isn't the fastest, but is still not a slouch and a video upgrade isn't going to work any fps miracles.

Thanks, I hadn't really thought about needing to look at the video card/chip but good to know i shouldn't have to worry about that.

So I am very confused now

I just attempted using the jumper suggestion by PD2JK to set the processor speed to 66MHz and now my computer is now shockingly fast. More than I'd expect whatever the difference between 50 and 66 MHz would be.

One of my benchmark scores tripled in one of the tools i tried

I had to have Doom at nearly the smallest window size but now it's playable at full size with UI. Warcraft was a slideshow and now it's smooth.