First post, by Gonduron
While building a high-end 486 retro-PC, I tripped over a L2-cache / SRAM DIP problem.
- I've got an Asus VL-I-486SV2GX4 mainboard.
- This mainboard came with eight pre-installed SRAM chips, 28-pins, 256 kByte Cache in total. Type is Winbond W24257AK-15, see datasheet attached.
- These DIPs work all ok.
- I want to upgrade to 1 MByte L2-cache total. I guess this won't give me a big boost; it's really just for the look and feel 😀
- I bought SRAM chips from a trustworthy UK vendor (The Micro Hut): Eight DIPs, 32-pins, type is ISSI IS61C1024-15N, see datasheet attached.
- I installed the chips in proper orientation and set the mainboard jumpers for 1 MByte total as written in the manual.
- Unfortunately, this did not work. At power-on black screen, no POST beep.
- I reverted to the 256 kByte setup. System now works ok again.
- I compared the datasheets of both SRAM chips: The ISSI chips have a different pinout 🙁
- I googled around and found a potentially suitable SRAM DIP, type Winbond W241024AK-15, see datasheet attached.
- Even though the pinout is almost the same, it does not match 100%: On the small Winbond chip pin28 is VDD (power supply), whereas on the big Winbond chip the same pin is CS2 (chip select).
1) Any idea whether the big Winbond chip will work or not?
2) Will the Mainboard jumpers take care of the slightly different pinout (VDD-pin on MB into CS-pin of SRAM)?
3) Do you know of any 1024k DIPs that will definitely work with this mainboard?
Thank you for your time 😀
My "Pixeli": Intel 486DX4-100 -- Asus VL/I-486SV2GX4 -- 16 MB -- Diamond Stealth64 S3 Vision868 2 MB VLB -- AWE64 Gold -- Roland LAPC-I and SCC-1 -- Adaptec AVA-2825 -- IBM 1 GB SCSI-2 -- Plextor 8x -- Teac 3,5" + 5,25" -- EIZO S2133