Hey guys,
I know this has been touched on before and I have read the other threads on similar subjects, but those threads are now locked to further posts and I just wanted some confirmation.
I just purchased an ST 16mhz Booster 2021, STF C070789 CPU relocator, 64pin socket and 16mhz capable CPU (pin headers etc I have in spades). This is to go into a 1040 STF C070789-001 Rev C1 with an installed Blitter. I will be doing the required mods/fixes and the motherboard has been fully recapped with a Recapped PSU with upgraded rectifier.
My question is, I currently have KAOS TOS 1.4.2 (English version) installed via 6 x M27C256-10F1 100ns EPROMs - will these EPROMs be fast enough to work with the 16mhz Booster? I don't require the TOS 2.06 decoding etc functions, just the 16mhz CPU acceleration.
Thanks for your help.
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ST Booster in C070789 with EPROM TOS
Re: ST Booster in C070789 with EPROM TOS
If they are genuine 100ns it should work.
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abraXXious
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Re: ST Booster in C070789 with EPROM TOS
- rubber_jonnie
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Re: ST Booster in C070789 with EPROM TOS
Almost any IC can be marked as something else so it's not a case of something being cheap enough they wouldn't bother, it's a case of risk vs reward. If they can make a profit then they will do it.abraXXious wrote: Thu Oct 23, 2025 8:27 amNow you have me worried.
Is fraudulent marking common in EPROMs? I know it is with CPU's etc, but I would have thought EPROMs are cheap enough that even the Chinese would not bother forging them.
I've had cheap 8 pin op amps from a trusted supplier on eBay that were re-marked and didn't work and they are cheaper than eproms.
Whilst the issue of fake ICs is out there, you just have to accept the risk.
I've had something like 80 RAM ICs from AliExpress and aside from some dead ones they were all genuine, so it's pot luck I'm afraid.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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abraXXious
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Re: ST Booster in C070789 with EPROM TOS
I guess I was assuming that the actual cost of resurfacing then re-stenciling chips would negate the benefit of selling such a cheap item under false pretenses, obviously labour is even cheaper than I assumed in China to make it financially viable to do this to such low value items.rubber_jonnie wrote: Thu Oct 23, 2025 9:03 amAlmost any IC can be marked as something else so it's not a case of something being cheap enough they wouldn't bother, it's a case of risk vs reward. If they can make a profit then they will do it.abraXXious wrote: Thu Oct 23, 2025 8:27 am
Now you have me worried.
Is fraudulent marking common in EPROMs? I know it is with CPU's etc, but I would have thought EPROMs are cheap enough that even the Chinese would not bother forging them.
I've had cheap 8 pin op amps from a trusted supplier on eBay that were re-marked and didn't work and they were cheaper than
I might get out the ole' TL866 and see if it has a function to test EPROM read speed.
- stephen_usher
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Re: ST Booster in C070789 with EPROM TOS
Given that they even remark TTL chips (pointlessly), which cost pennies, there's no cost point where they don't do it.
It's silly really as it costs them both money and reputation. Far better to have genuinely marked reclaimed chips which have been cleaned and gone through a QA test, which would still be cheaper than remarking, and gain a good reputation and hence more return purchasing.
It's silly really as it costs them both money and reputation. Far better to have genuinely marked reclaimed chips which have been cleaned and gone through a QA test, which would still be cheaper than remarking, and gain a good reputation and hence more return purchasing.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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abraXXious
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Re: ST Booster in C070789 with EPROM TOS
Exactly what I was thinking. I can understand the theory of ripping consumers off for a quick buck by rebranding low cost chips as significantly more desirable higher cost chips... but it seems pretty stupid and short sighted to ruin your commercial reputation over pennies.stephen_usher wrote: Thu Oct 23, 2025 9:17 am Given that they even remark TTL chips (pointlessly), which cost pennies, there's no cost point where they don't do it.
It's silly really as it costs them both money and reputation. Far better to have genuinely marked reclaimed chips which have been cleaned and gone through a QA test, which would still be cheaper than remarking, and gain a good reputation and hence more return purchasing.
Still, Chinese is Chinese.
Re: ST Booster in C070789 with EPROM TOS
If you come from China they are most likely reprinted, changed speed grade as minimum.
I suspect all the EPROMS I have purchased over the past few years they are supposed to be SGS brand, but I think they are reprinted TI parts.. The print doesn't look like it used to and the arrays window was generally a lot smaller on the TI parts. But I never conclusively looked into it all.
Expensive parts like the 060 CPUs they reprint the lot. Even genuine rev 6 chips they reprint as rev 6!
Cheaper parts like GALs I had 100 a few years ago, it was like they was all dummy ICs.. No resistance between any pins whatsoever and the chip identifier couldn't detect anything either.. A lot of GALs are reprinted as -7 when they could be anything. I wrote loads about that when I was developing the STE booster.
Like I've been saying lately, China prices are getting more expensive than they are used parts and a lot of them are faulty or not as they appear to be.. By the time you pay shipping and tax.. There's not much price difference in just buying genuine parts from my legitimate brokers.
I suspect all the EPROMS I have purchased over the past few years they are supposed to be SGS brand, but I think they are reprinted TI parts.. The print doesn't look like it used to and the arrays window was generally a lot smaller on the TI parts. But I never conclusively looked into it all.
Expensive parts like the 060 CPUs they reprint the lot. Even genuine rev 6 chips they reprint as rev 6!
Cheaper parts like GALs I had 100 a few years ago, it was like they was all dummy ICs.. No resistance between any pins whatsoever and the chip identifier couldn't detect anything either.. A lot of GALs are reprinted as -7 when they could be anything. I wrote loads about that when I was developing the STE booster.
Like I've been saying lately, China prices are getting more expensive than they are used parts and a lot of them are faulty or not as they appear to be.. By the time you pay shipping and tax.. There's not much price difference in just buying genuine parts from my legitimate brokers.
- rubber_jonnie
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Re: ST Booster in C070789 with EPROM TOS
Well if you consider the resurfacing an re-stencilling could be done by laser super quick and automatically, the labour costs are minimal and with lots of people buying IC's for retro hobbies, it's probably worth it if they can shift parts in bulk.abraXXious wrote: Thu Oct 23, 2025 9:10 am
I guess I was assuming that the actual cost of resurfacing then re-stenciling chips would negate the benefit of selling such a cheap item under false pretenses, obviously labour is even cheaper than I assumed in China to make it financially viable to do this to such low value items.
I mean I agree, it seems unsustainable financially, but still it goes on.
As for reputation, I don't think they care as they vanish and appear under another name, or offload stock as fast as possible and let others take the reputational risk.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...