You can add the PC Chips M577 to your MVP3 list. The M577 (as far as I know) always comes with 1MB of cache.

FIC PA-2013 512K and 1M available

Actually 2M.

I did this with some DFI mainboards recently:
Re: DFI K6XV3+/66 L2 and K6BV3+/66 L2 cache upgrade

It easiest when the mainboards footprint for the TAG chip allows 32-pin chips.

The Serpent Rider wrote on 2023-06-22, 08:49:

FIC PA-2013 512K and 1M available

Actually 2M.

I´m not so sure here, since the PA-2013 has a 28-pin TAG chip. All 4 chips populated on a PA-2013 probably means 4 x 256K chips.

https://www.anandtech.com/show/1
https://www.tomshardware.com/reviews/socket-7 … 1998,79-10.html

The Serpent Rider wrote on 2023-06-22, 12:01:

https://www.anandtech.com/show/1
https://www.tomshardware.com/reviews/socket-7 … 1998,79-10.html

I cannot find a picture with a 32-pin TAG. Of course it´s possible there was a (later) revision with full TAG support.

Edit / correction: I did find a picture of a full featured PA-2013

So Serpent Rider is right - there´s a 2MB version of the PA-2013 and the necessary TAG-chip is provided.

Actually, looking at a few (not so good) pictures of the Shuttle HOT-597, there seems to be a 28pin TAG-chip, but there are four pins unused on the board.
Officially, there was only a 512K and 1MB version of it. Also, there is one "affordable" on ebay (512K).
A picture on TRW shows T35L6464A-Q5 for cache but I can't make out the TAG ram: https://theretroweb.com/motherboard/image/hot … 84599209677.jpg

The TAG chip is a 256K one, for 2MB cache you could replace it by a 512K (32-pin) chip. There are also empty jumper / resistor positions nearby so I would _assume_ a 2MB upgrade can be done, but be prepared to do some research to find the jumper (zero ohm resistors) settings you need. And there´s a risk of failure if there´s a faulty layout or if you cannot find the correct settings.

majestyk wrote on 2023-06-22, 12:14:

So Serpent Rider is right - there´s a 2MB version of the PA-2013 and the necessary TAG-chip is provided.

https://akiba-pc.watch.impress.co.jp/hotline/ … 26/newitem.html https://akiba--pc-watch-impress-co-jp.transla … &_x_tr_pto=wapp

FIC PA2013
(MVP3,ATX,2MB,AGP1
　,PCI3,PCI/ISA1,ISA1,DIMM3)
13,800 Tsukumo PC Main Store II
14,800 i2 DOS/V Senka Tokyo 3rd store
15,800 BLESS
　New version with secondary cache increased to 2MB. This is the first Socket 7 motherboard with 2MB secondary cache. The previous maximum was 1MB.
　The PMSRAM, which is used as the secondary cache, has a sticker with the letters "MT63V3212Q-5 9842A", which seems to be the model number, attached.

did upgrade from 512k to 1m for my TEKRAM P5M3-A+

the board did not accept a new 512k tag ram so i just upgraded the cache chip. (a bios limitation?)

board can run @133mhz with cache enabled.

all you have to do is just replace cache chip and switch 0-ohm resistor R118->>R117

A 512K TAG chip is needed for 2MB L2 cache ONLY.
When upgrading L2 from 512K to 1MB there´s no need to replace the TAG chip, 256K is sufficient.

the idea was to get 2mb. unfortunately board detect only 1024 mb and it is not booting.

(no initialisation for tag in bios?)

there were no 2mb tekram boards in the wild.

That is nice work soldering SMD chips so close to the plastic socket! Thanks for sharing your result. I don't think there are many 133MHz socket 7 boards working with cache. Do you have a good source for those cache chips? I recently picked up an epox board that I'd like to try upgrading.