64MB SIMM for LC475 - compatibility

[croissantking]

Is there any information available about which 64MB SIMMs may work in an LC475? I am thinking about picking up one of these: (eBay link)

 

[stynx]

They look good to me. They are 3.3V EDO chips with a voltage regulator and should work.

 

[frontein1]

I'm trying to find the link for what I bought for my LC475/Q605. I went for the 128MB SIMM. But importantly I think I bought the one labeled "angled socket" so it would fit correctly.

 

[Callan]

I ended up using a 128meg simm I bought off ebay for cheap on my lc475.

128MB 72 Pin EDO Memory SIMM 5V 3V 60ns | eBay

Find many great new & used options and get the best deals for 128MB 72 Pin EDO Memory SIMM 5V 3V 60ns at the best online prices at eBay! Free shipping for many products!

ebay.us

The ram works great except for the long memory test. Nipped that in the bud by using frontein1's rom image to disable the memory test. I've been using it over a month now with no issues. It works a treat!

F

Thread 'Testers Needed: Modified ROM for LC475/Q605'

Aug 27, 2025

For those with LC475/Q605-type Macs (ROM checksum FF 74 39 EE), a working SIMM slot, a SIMM programmer, and an available 8MB SIMM..... I would appreciate feedback on the attached ROM.

Firstly, thanks goes to @JDW @Jockelill and @WillJac for doing some initial testing and providing feedback. An important lesson we learned during testing is to fully reset your PRAM before using a new ROM. Especially if the new ROM uses PRAM settings (such as this one).

Secondly, I want to specifically point out that I am using a modified version of the CDEV (control panel) that...

• frontein1
• Replies: 38
• Forum: Mac II, Quadra & Centris

 

[frontein1]

I've been using it over a month now with no issues.

Glad to hear it is working well for you! Take a look at the ROM downloads on the CayMac site. The 040 ROMs are past beta now up to v1.0. Still working on finishing the 030 version.

https://ko-fi.com/caymacvintage/shop