AFAIK, bank 0 on the left side (curently empty sockets)

stalk3r wrote:

They seem to be low quality, the marking come off as soon as you touch it, etc.

They are most likely just a block of plastic...

Tronix wrote:

AFAIK, bank 0 on the left side (curently empty sockets)

Nope, sockets U5-U8 are on the right, I have checked that. The table in the manual is misleading a bit.

derSammler wrote:

stalk3r wrote:

They seem to be low quality, the marking come off as soon as you touch it, etc.

They are most likely just a block of plastic...

In this case the PC would boot as the sockets were empty 😀

Not if the pins are all connected to each other. 😉

These 10ns ISSI parts are supposedly remarked 3.3V parts. They get very hot when they do run and in long term are very unhealthy for the hardware they're in. I'll have a solution ready in not so far future

Maybe those chips have all pins with NC, but you have a real branded tag chip there, right? Maybe the motherboard doesn't boot with empty sockets yet having the tag chip?

GigAHerZ wrote:

Maybe those chips have all pins with NC, but you have a real branded tag chip there, right? Maybe the motherboard doesn't boot with empty sockets yet having the tag chip?

It does, I removed the chips leaving the tag chip only in there. I suspect one or more of them is DOA, or they are indeed just worthless plastic blocks.

https://www.aliexpress.com/item/IS61C1024-15N … 2805450062.html

I bought 15 IS61C1024-15N from that listing. They seem to be genuine and stay cool, but 5 of 15 were dead on arrival.

That ISSI logo doesn't look very promising.

Stay away from these vinegar srams - many are dead or not working correctly. Feipoa seemed to have had a lucky streak years ago and his srams, albeit generic, do work as expected.

There may be batches that are ok, but in my experience many ICs are unreliable and caused the system to be unstable. Look for genuine srams on ebay from non chinese sellers who post real photographies of their goods.
Tiido's solution is ulimately the only viable one if you want to have access to genuine and faster parts.

Mine performs very stable too, it does not boot 10 out of 10 attempts. Well, what else can someone expect for 1$/IC shipped.

yep I am also expecting for Tiido to release these cache chips...
I too have got those chinese rebranded srams - they work for tests but I don't use them in any system... I just don't trust them that much 🤣

stalk3r wrote:

I bought these cheap 10ns 32pin DIPs to upgrade the current 256k to 512k , but the PC does not even boot with it... I know that the TAG is slower but it should boot regardless. The jumpers are good. Has anyone tried these? They seem to be low quality, the marking come off as soon as you touch it, etc.

How many motherboards have you tried these SRAM modules in? How many modules did you buy? Did you try different modules?

I have a lot of these modules. Super Fast 486 Cache - 10 ns Mine do not get much hotter than other components on the motherboard and are certainly not hot to the touch. I did find that about 1 in 10 were bad though. Once I weeded out the bad chips with an SRAM tester, the remainder have remained working fine. I suspect you have one or more bad modules. If you don't have an SRAM tester, try rotating through the pieces. And try another motherboard, preferably one that is noted elsewhere as working with 1024K modules. I've noticed that some old motherboards have jumper settings for larger caches, but for whatever reason, do not actually work with larger [tested good] caches.

Tiido, do you have a thread on these SMD to DIP SRAM PCB's? Are there real 10 ns modules? And is a VRM required on the PCB?

I made a thread at one point to gauge interest, I'll resurrect it once I have everything sorted out. The chips are all from big distributors, no ebay or chinese sources, PCBs have just 1:1 pin mapping with a ground plane and spot for decoupling caps.

I bought ten ISSI IS61C1024-10N chips in aliexpress. One was dead, the other nine worked (one of the nine would prevent the computer to boot if it was placed in the first socket, but it worked in the other three sockets). My bet is that they are not original ISSI chips, and that they are not 10 ns chips. I think they are rebranded so that they can be sold more easily.

I had the same issue with seemingly same SRAM chips which in my case I sourced off Ebay. The poor logo printing suggests to me these are the same. I could not make them work at all, most likely fakes or pieces of garbage.

You need to test them in an sram tester. Many eeprom
programmers have an sram test function.