Correction 9:26 about CLKMUL: The jumper on the 5x86 works in reverse compared to the DX4. Jumper position 2-3 sets it to 4x, open (or 1-2 on my motherboard) sets it to 3x. This was also wrong on the silkscreen table. I fixed it in the latest revision.
The videos on the 486SocketBlaster make me wish I had been able to keep my old 486 PC. I had a 5v to 3.3v adapter just like this in that PC back in the early to mid 90's and used it with an AMD 5x86 CPU for a couple of years. It wasn't a perfect solution but for a teenager who had limited money it was a great solution!
That's been my question the whole time. Does no one know that they used to sell these things? I have two of the socket type, and one of those SMD-on-a-PGA upgrades. I am pleased that new ones are being designed, as they are getting harder to find.
Aye, 3.45v should be a good set voltage for things like this. 3v 486s that want 3.3v have a decent tolerance that 486's which want 3.45v doesn't really have. I've run an 5x86 100mhz off of an 1084-3.3 and it works a treat. The regulator doesn't even get warm.
@@scrap_computing Have used this type myself for all kinds of stuff. I wouldn't recommend them beyond 1A though. But it's certainly worth a try. With some 15ns cache and 60ns DRAM it should run with optimal timings at 40MHz. It's going to be a beast.
Hi, I was thinking, A viewer left this comment: " For the 4x multiplier just isolate the clkmul pin of the cpu from the board and manually pull it to ground (or check if it goes to any resistor or jumper like the clock generator did). Ive literally played the same game on mine which is a siemens nixdorf d819 motherboard. I just connected it to chassis with a wire and its happily running at 160mhz giving around 1300ish realtics in doom. " - So, Instead of soldering a bodge wire, would it be easy to change the Socket blaster board to have an extra pin header with a jumper? The original interposer from back in the day had a pin header marked AMD2X. I don’t have one to check, but maybe, that's exactly what we need?
The CLKMUL jumper position 2-3 grounds the CLKMUL pin of the CPU. On the Am5x86 this enables a multiplier or 4x, but on the DX4 it reduces the multiplier to 2x. Ah, I think the CLKMUL table on the silkscreen is wrong. It should say 2-3: 4x and N/C: 3x. I will fix this. This is a good opportunity to add the write-back header too.
I believe the 5x86s run normally at 3.45 volts, and they do really need a heatsink. Worn capacitors on the motherboard can causes crashes and instability too, and 386 and486 systems are starting to reach that age. I suspect yours are on they way out. -You should not need 50uf on an adapter to run an AM5x86.- EDIT: Well, it would appear I am dead wrong. I just pulled one of my adapters out and sure enough, there are *2* 6V 47uf caps plus a 16v 22uf cap on it. I also took a look at my Trinity upgrade CPU, which is a similar idea, but uses an SMD 5x86. It has 5 10v 10uf caps on it, plus a smaller 6th cap whose value I can't read. On an unrelated note, have you thought about adding pins on the edge of your socket to try a Pentium Overdrive?
Yes, they definitely need a heatsink, and I did use one for testing, though I did not show it in the video. I was surprised too that it needs so high capacitance values. Thanks for sharing the capacitor values. I have not looked into Pentium overdrives. Wouldn't they need to be supported by the chipset?
@@scrap_computing I'm not 100% certain what Pentium Overdrive support really entails. I put a socket down on the solder pads of a motherboard I had and while it did boot, it identified it as some sort of "Intel SX" CPU, and ran with write through cache, but otherwise did indeed work.
5x86-P75 should have a WB L1 cache, which was disabled on your system. When enabled, you get a bit of performance boost and speedsys will report it's a WB CPU.
Hey. I would recommend looking my fork of this device. You don't have to do the built in regulator but do look at the 4 layer design of it. With some help from people who really know what they are doing, we pumped out that 4 layer design that should have better signal integrity and power delivery with power planes instead of traces. I never got one made myself since i don't currently have a use for such devices. Nice video, nice idea but that cheap regular is a little iffy.
Hey....love the video. Since youve made the socket blaster i wonder how complex it would be to build a socket device where a QFP package 486 could be used in a socketed 1, 2, or 3 motherboard.
Nice project, *but* the Overdrive's FPU is extremely powerful. Depending on whether you need Integer or FPU performance it's a no brainer which one is better. Also the 83MHz variant of the ODP can very often run stable at 100MHz.
Perhaps you are thinking of the Pentium Overdrive, which is using a better core. These are indeed a lot faster. The 486 Overdrive CPUs are based on the same 486 cores and are meant to be used on older sockets that cannot provide 3.3V.
@@scrap_computingYup, the original Intel Overdrive is kinda meh in my book. Still a major improvement, but if a Pentium Overdrive is no option I'd go with AMD if possible.
Hi. Are you aware the some capacitors need to have their capacitance derated when running at higher voltages close to their ratings? So for example a 1uF ceramic cap rated for 6.3V, is not actually 1uF when running at 5V.
2 Questions. Is everything updated for all you need to build this and are you going to try using a Cyrix 5x86 CPU to see if any more changes need to be updated?
I haven't made changes to this project for quite a while, but that doesn't mean that things are not going to change in the future. It's in a pretty stable state though, if this is what you are asking. I don't own a Cyrix 5x86, but if I ever get my hands on one I will try it on.
@@scrap_computingYes. When you used the AMD 5x86 133 you added more components to the underside of the adapter/regulator. Do I just need to follow the video or is your information fully updated and plus is a premade version available to purchase. I don't have the faintest clue on all the comments that I need to purchase are, plus I don't have any as soldering skills nor do I know anyone that can make one up for me. I definitely need to be able to purchase these rvm fully made.
@@clintthompson4100 The information on the project's page should be adequate, it lists all components needed. This is a tricky board to make and requires good soldering skills. Others have reported that they had to scrap several boards because of soldering mistakes. I am not selling these boards myself and I am not aware if anyone else is selling them.
There are only 4 SMD capacitors on the board, and the pads are optimized for hand-soldering, so it is not too hard. Just solder one side first and then the other.
@@scrap_computing well, I have made two attempts. On the first attempt, I made an unfixable solder bridge and had to scrap it about halfway through, and on the second attempt my AM5x86 won't fit the socket I made. This is a precision job for sure, and I don't think I have a steady enough hand to get it right. Are you sure you don't want to sell these? I think you could make some serious money if you did, at least while the 486 is popular in the retro community.
@@Megatog615 Sorry to hear that. It is indeed a bit tricky, but it is not impossible. I made similar mistakes myself when building it. You may need to adjust the CPU pins a bit to make it fit the socket, if the socket is not perfect. It is a bit tricky getting it in the first time. Just like most folks in this hobby I am not an expert in soldering, and it takes me a long time to make one, and the result is not great. So I could not possibly sell them.
Correction 9:26 about CLKMUL: The jumper on the 5x86 works in reverse compared to the DX4. Jumper position 2-3 sets it to 4x, open (or 1-2 on my motherboard) sets it to 3x. This was also wrong on the silkscreen table. I fixed it in the latest revision.
The videos on the 486SocketBlaster make me wish I had been able to keep my old 486 PC. I had a 5v to 3.3v adapter just like this in that PC back in the early to mid 90's and used it with an AMD 5x86 CPU for a couple of years. It wasn't a perfect solution but for a teenager who had limited money it was a great solution!
That's been my question the whole time. Does no one know that they used to sell these things? I have two of the socket type, and one of those SMD-on-a-PGA upgrades.
I am pleased that new ones are being designed, as they are getting harder to find.
This channel is a gem. Once you finish with super socket 7 asus, would be great to see a video with socket 5/7 motherboard
I love this community.
They are amazing and developing everything. All those kids that grew up into retro engineerhood :)
By the way, the 5x86 says "3.45VOLT" along with "HEATSINK AND FAN REQD" on some versions of the chip. I think the right voltage is 3.45 volts.
Makes sense.
Aye, 3.45v should be a good set voltage for things like this. 3v 486s that want 3.3v have a decent tolerance that 486's which want 3.45v doesn't really have.
I've run an 5x86 100mhz off of an 1084-3.3 and it works a treat. The regulator doesn't even get warm.
Seen this on another channel. Its sad the channel owner didnt give you a shoutout for this wonderful piece of work.
Yeah, but his video is great, because he is explaining a lot of things in great detail!
Excellent work, love seeing iterations with results.
Absolutely can't wait to make one of these. Thanks for showing the whole process as well!
For 160MHz, I always had to increase the voltage to about 3.6V.
I am not sure this cheap voltage regulator can handle overclocking, but I should give it a try :)
@@scrap_computing Have used this type myself for all kinds of stuff. I wouldn't recommend them beyond 1A though. But it's certainly worth a try. With some 15ns cache and 60ns DRAM it should run with optimal timings at 40MHz. It's going to be a beast.
Thanks, Bonzi Buddy.
haha just ordered a 5x86 133 before they go way up in price
Cool channel, man. 👍
Hi, I was thinking, A viewer left this comment:
"
For the 4x multiplier just isolate the clkmul pin of the cpu from the board and manually pull it to ground (or check if it goes to any resistor or jumper like the clock generator did). Ive literally played the same game on mine which is a siemens nixdorf d819 motherboard. I just connected it to chassis with a wire and its happily running at 160mhz giving around 1300ish realtics in doom.
"
- So, Instead of soldering a bodge wire, would it be easy to change the Socket blaster board to have an extra pin header with a jumper?
The original interposer from back in the day had a pin header marked AMD2X.
I don’t have one to check, but maybe, that's exactly what we need?
The CLKMUL jumper position 2-3 grounds the CLKMUL pin of the CPU. On the Am5x86 this enables a multiplier or 4x, but on the DX4 it reduces the multiplier to 2x.
Ah, I think the CLKMUL table on the silkscreen is wrong. It should say 2-3: 4x and N/C: 3x.
I will fix this. This is a good opportunity to add the write-back header too.
@@scrap_computing It worked! Thank you :)
I believe the 5x86s run normally at 3.45 volts, and they do really need a heatsink. Worn capacitors on the motherboard can causes crashes and instability too, and 386 and486 systems are starting to reach that age. I suspect yours are on they way out. -You should not need 50uf on an adapter to run an AM5x86.-
EDIT: Well, it would appear I am dead wrong. I just pulled one of my adapters out and sure enough, there are *2* 6V 47uf caps plus a 16v 22uf cap on it. I also took a look at my Trinity upgrade CPU, which is a similar idea, but uses an SMD 5x86. It has 5 10v 10uf caps on it, plus a smaller 6th cap whose value I can't read.
On an unrelated note, have you thought about adding pins on the edge of your socket to try a Pentium Overdrive?
Yes, they definitely need a heatsink, and I did use one for testing, though I did not show it in the video.
I was surprised too that it needs so high capacitance values. Thanks for sharing the capacitor values.
I have not looked into Pentium overdrives. Wouldn't they need to be supported by the chipset?
@@scrap_computing I'm not 100% certain what Pentium Overdrive support really entails. I put a socket down on the solder pads of a motherboard I had and while it did boot, it identified it as some sort of "Intel SX" CPU, and ran with write through cache, but otherwise did indeed work.
5x86-P75 should have a WB L1 cache, which was disabled on your system. When enabled, you get a bit of performance boost and speedsys will report it's a WB CPU.
Yeah this is in the TODO list for the next revision of the Socket Blaster :)
Hey. I would recommend looking my fork of this device. You don't have to do the built in regulator but do look at the 4 layer design of it. With some help from people who really know what they are doing, we pumped out that 4 layer design that should have better signal integrity and power delivery with power planes instead of traces.
I never got one made myself since i don't currently have a use for such devices. Nice video, nice idea but that cheap regular is a little iffy.
Yeah, I should give it a try. Sadly, I haven't been following the vogons thread much, so I need to catch up.
Why would number of layers make any difference when there are almost no traces to speak of in this 1:1 adapter?
Can you post a link to your fork?
Hey....love the video. Since youve made the socket blaster i wonder how complex it would be to build a socket device where a QFP package 486 could be used in a socketed 1, 2, or 3 motherboard.
This shouldn't be too hard as long as the package can fit inside the innermost row of pins.
Nice project, *but* the Overdrive's FPU is extremely powerful. Depending on whether you need Integer or FPU performance it's a no brainer which one is better. Also the 83MHz variant of the ODP can very often run stable at 100MHz.
Perhaps you are thinking of the Pentium Overdrive, which is using a better core. These are indeed a lot faster.
The 486 Overdrive CPUs are based on the same 486 cores and are meant to be used on older sockets that cannot provide 3.3V.
@@scrap_computingYup, the original Intel Overdrive is kinda meh in my book. Still a major improvement, but if a Pentium Overdrive is no option I'd go with AMD if possible.
Could a similar principle be used to make an adapter to run a later K6-2 or the like on a regular Socket 7 motherboard, like with a i430 chipset?
Yes, but socket 7 has more dense pins, so building an adapter is much more challenging.
Hi. Are you aware the some capacitors need to have their capacitance derated when running at higher voltages close to their ratings? So for example a 1uF ceramic cap rated for 6.3V, is not actually 1uF when running at 5V.
I was not aware of that, thanks for sharing!
Can you play high quality mp3 or video CD using this?
2 Questions. Is everything updated for all you need to build this and are you going to try using a Cyrix 5x86 CPU to see if any more changes need to be updated?
I haven't made changes to this project for quite a while, but that doesn't mean that things are not going to change in the future. It's in a pretty stable state though, if this is what you are asking.
I don't own a Cyrix 5x86, but if I ever get my hands on one I will try it on.
@@scrap_computingYes. When you used the AMD 5x86 133 you added more components to the underside of the adapter/regulator. Do I just need to follow the video or is your information fully updated and plus is a premade version available to purchase. I don't have the faintest clue on all the comments that I need to purchase are, plus I don't have any as soldering skills nor do I know anyone that can make one up for me. I definitely need to be able to purchase these rvm fully made.
@@clintthompson4100 The information on the project's page should be adequate, it lists all components needed.
This is a tricky board to make and requires good soldering skills. Others have reported that they had to scrap several boards because of soldering mistakes.
I am not selling these boards myself and I am not aware if anyone else is selling them.
Would it be possible to buy one of these from you? I'm not comfortable with SMD soldering yet.
There are only 4 SMD capacitors on the board, and the pads are optimized for hand-soldering, so it is not too hard. Just solder one side first and then the other.
@@scrap_computing well, I have made two attempts. On the first attempt, I made an unfixable solder bridge and had to scrap it about halfway through, and on the second attempt my AM5x86 won't fit the socket I made. This is a precision job for sure, and I don't think I have a steady enough hand to get it right. Are you sure you don't want to sell these? I think you could make some serious money if you did, at least while the 486 is popular in the retro community.
You may find a local builder who would do it (and love it)
@@Megatog615 Sorry to hear that. It is indeed a bit tricky, but it is not impossible. I made similar mistakes myself when building it.
You may need to adjust the CPU pins a bit to make it fit the socket, if the socket is not perfect. It is a bit tricky getting it in the first time.
Just like most folks in this hobby I am not an expert in soldering, and it takes me a long time to make one, and the result is not great. So I could not possibly sell them.
speedsys getting a little confused about the graphic installed, claims its ISA CL-GD5422 :)
Could you stack some capacitors in parallel for better filtering?
Yeah you could even place a huge capacitor on the ExtPWR header :D
Pentium Overdrive??? Hahahaha
I think we need this.... ;)
what about cooling?