Cache is Installed and it seems to be running - and W95a feels a bit snappier though that could just be the 'placebo effect'. Board looks 'legit' with video, ram and cache sockets all populated.

It took a few tries, and I started with the modules at the incorrect end of the sockets [bonehead move after I though about it - I aligned the 28 pin with the 32 pin, rather than the 28th], but after it was setup correctly it booted fine. Jumper instruction printed on the board were fine - only two options for 512k so there wasn't much to it.

Cache is enabled in bios but bios doesn't display how much it is reading. Is this normal for 468 era machines?

Now to drop the drive caddy in and see if I can operate off it without issue.

EDIT: A little setback. I pushed the modules in to fully seat them after it tested good and a corner pin on one of the modules snapped off - it wasn't seated right and the extra push broke it. The system wont boot past POST so looks like I need a new Winbond W24257AK-15 [94340] part. eBay...

EDIT 2: Super glue... pretty funny but actually got the pin glued back on and it booted. Waddya know, but still will want a replacement module tho..

My 486 displays the amount of cache during POST. I don't know about others. You can check it for yourself with cachechk. (http://www.minuszerodegrees.net/software/software.htm).

Going from zero cache to 512K should be obviously not placebo, in a game that taxes the CPU. e.g. DOOM. I found that going from 128K to 256 was a significant improvement on my board. If in doubt that you're actually seeing more frames, you can use 'doom -timedemo demo3' to actually count the frames (realtics = frames * 35).

Definitely replace that chip with a broken leg. I always buy a few spare ICs when I shop, just in case.

Haha yes, I posted my comments before running any games - but navigating W95 definitely felt 'snappier'. But I kick myself for breaking the pin as it was part of a nice matched set. Are there places that still supply these vintage pieces?

Hmmm... cache is not being reported by cachechk or speedsys so i'm not sure it's set up right yet, or if it's not 'fake'. I was mistaken in thinking it was 512k - i'm thinking now that its eight 32k x8 chips which is 256k. But jumpers set to 256 don't solve the problem either. Also tried disabling cache write back in bios but that had no effect.

Looking at the mobo more closely for jumpers that may needed setting. The diagram is clear about how to set the amount of ram but perhaps there is a jumper to enable external ram too?

The problem is the TAG module. Seems it's 16k [Aster AE88128ak-15, I'm deducing the "128" = 16k] and I need a 32k for an array of eight 32k dips [W24257AK-15] on my board. If I had an 8k TAG I could run four 32k units in Bank 0 for 128k cache, but I don't have one of those either. I'm *just* starting to get the hang of this I think 🤣...

I will say that all the pertinent jumper info is printed right on the mobo which is nice. I also discovered that the board Epson used in their ACTION 7000SER pc has a very similar layout and a jumper configuration identical to my Elitegroup UP8810a VIO rev 3.3/3.6., so documentation of sorts is at Stason.org if hidden a little.

With newly acquired IC extractor 'claws' and a fresh set of NKK 32kb cache modules I am now up and running @ 256kb L2 - smooth as silk.
So the basic work is now complete:

Fully populated cache
maxed out video ram @ 2 mb
drive caddy for data transfer [via a usb dock, so I can can also fully backup the disk and do other disk work off the machine]

To do: game/data setup and conventional memory config.

Since getting the 486 strange things have begun to happen... I found myself tracking Roland Sound Canvas bids on eBay...

A DX2-66 system is a great choice.

Roland MT-32 and Sound Canvas SC-55 are also perfect with a 486.

64MB seems like a bit of overkill unless your running windows 95 or windows 98.

How much of the 64 is cache-able on your motherboard along with the 256k cache?

How about some speedsys, pcpbench, cachechk bench screenshots?

I'm running w95a so 64 ram seemed a reasonable compromise with period correctness, though that's heavily influenced by the fact I don't have 8mb sticks or I'd probably go with 32. But I wanted to populate all 4 slots and 16s are the smalled sdram I have on hand.

As far as how much ram is cache-able I don't know yet. The bios has settings for bios/video cache-ing, which are enabled, and 'Shadow' stuff I'm not familiar with, so I guess I'll have to run speedsys/cachechk to see what's actually going on in there.

One thing I did notice is that per Speedsys the TI 486dx2/66 is jumpered to Cyrix and running at 75.7mhz [factory set I'm pretty sure], which sounds like a little OC business to me. Chip gets hot to touch but not crazy. I like the graphics or I'd slap a passive sink on it right now.

Biostar RAM is such good option to choose for computer.

i comfort by using this company computer peripheral devices.

The rig is running very smooth per previous posts: 256kb cache/2mb Cirrus Logic vram added/64mb system ram. Still haven't tackled conventional memory yet [other 'pressing' PC projects] and not sure if the dos drivers for the on-board ESS-1868 for will permit 600+ kb free, but we'll see. I'm looking to keep the 486 simple and if I can avoid installing a dedicated sound card I'll take it.

For $30 this little AST 486dx-66 is a blast - clean as a whistle too.