FPU Options
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FPU Options
Anyone got a lead on non-relabelled FPUs? I seem to always get ones that don't like >33MHz :s
Re: FPU Options
I purchased a couple from here and they both seem fine at 50Mhz:
https://www.ebay.co.uk/itm/202667387551
https://www.ebay.co.uk/itm/202667387551
Re: FPU Options
Hmm maybe I'm just unlucky - they look like the same generic China warehouse ones that I've been getting (from other sellers).PaulJ_2.0 wrote: ↑Fri Jun 14, 2019 11:44 pm I purchased a couple from here and they both seem fine at 50Mhz:
https://www.ebay.co.uk/itm/202667387551
If you are game, would your rub the surface with some isoproyl alcohol and see if the markings remain or disappear? On mine a rub with IPA and the markings are gone
Re: FPU Options
I just rubbed with IPA and the markings are still there.dalek wrote: ↑Sat Jun 15, 2019 2:10 am Hmm maybe I'm just unlucky - they look like the same generic China warehouse ones that I've been getting (from other sellers).
If you are game, would your rub the surface with some isoproyl alcohol and see if the markings remain or disappear? On mine a rub with IPA and the markings are gone
You may just have been unlucky. Both of mine are absolutely fine and only just get warm at 50MHz
Re: FPU Options
The majority of FPUs I've got from China haven't been relabelled but even then it's about 1 in 3 failures (no boot) so unfortunately it's a case of order more than you need.
Btw, I've had 20s that work at 50mhz.
Btw, I've had 20s that work at 50mhz.
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Re: FPU Options
My personal preference for this sort of thing is to avoid any seller that references China, since its probably an indication you'll be taking pot luck with whatever you're buying.
You might get a 68882 that'll run @ 50Mhz, but you might get something that isn't actually a 68882 at all, and won't work at any speed.
I'd suggest looking for individual sellers who are selling small amounts, and whose other items are also computer related. The seller in that link has a ton of other stuff such as household goods and beauty products that just shout that they are selling whatever they can get their hands on.
I got a pair of 40Mhz 68882s or just £10, both 100% fine, using the approach above.
You might get a 68882 that'll run @ 50Mhz, but you might get something that isn't actually a 68882 at all, and won't work at any speed.
I'd suggest looking for individual sellers who are selling small amounts, and whose other items are also computer related. The seller in that link has a ton of other stuff such as household goods and beauty products that just shout that they are selling whatever they can get their hands on.
I got a pair of 40Mhz 68882s or just £10, both 100% fine, using the approach above.
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...