Hot Plate

Step 4: Preparing the hot plate

locate the ground pins in your CPU and that can be done by reviewing the CPU data sheet or simply by the devastating trial and error.

Cut the USB wire and pass it through the hole you made previously in the base.

Strip the USB cable and locate the black and red weirs (black wire = ground, Red wire = +5V). You can cut out the white and green data weirs for more space.

Now connect the black wire to the ground pins and the red wire to voltage pins.

The best way to attach the weirs to the pins of the CPU is to cut the wires without striping them and then slide the pins inside.

Finally, you have to attach the CPU to the grill by Epoxy

Enjoy.

 

 

Comments

[pclever1]

I just tried this myself and the cpu got up to 96F and was able to melt chocolate. However the cpu clearly states that it runs at 1.525V. I tried it again latter and it want working (I checked the connections). Do you think I fried the cpu?

I used a phone charger for this that runs at 500ma (also 5V).

[umerji1000]

could someone please help me find the voltage and ground pins on my cpu.
here is the dash sheet: http://download.intel.com/design/celeron/datashts/30235305.pdf

[jbird123]

Nice tut!

I found the datasheet for a CPU that I'm looking at on eBay. It states "For clean on-chip power distribution, the Celeron processor on 0.13 micron process has 85 VCC (power) and 181 VSS (ground) input", does that mean I can solder the power wire to any one of these 85 VCC pins, and the ground wire to any one of the 181 VSS pins? Or will mine have a specific one that needs wiring to? Or maybe I'm not undeerstanding the statement correctly?

Also, when done would I be able to plug this into something such as an iPhone charger, I believe they are 5v?

[emilsegna]

Do anyone have pinout for Pentium 4 socket 775

[Computothought]

You might try the Intel web site as they usually have the details on all their cpu's.

[bhuot]

Check on the CPU itself, the model number and have it correspond to the page on that URL:
http://www.intel.com/support/processors/pentium4/sb/CS-029963.htm

[nakayanGD]

how to locate ground pins and voltage pins in Intel pentium 133

[deamonlord]

PLEASE can someone tell me which are the ground and voltage pins on a pentium 1 processor? I found a datasheet through google but it went over my head. If someone understands that techie language, please help me!

[RAMZI_PC]

hello
can i use an old CPU, like 368 one or 486

[TRAXXX]

work good at 10v 1A :D hehehehe it s hot

[M4industries]

0.o How did you get 10v 1a from a standard USB port?

[nopalboy]

maybe with 2 usb ports

[jamster545]

I think he means he hooked it to a different power supply. That would blow that processor pretty quick, i'd think.

[threepwood]

Hello! I Have an old amd duron 800 cpu, and I want to make that, but I have a little problem...: can´t find the voltage and ground pins. I´ve searched the datasheet, but all i could was lots of names and numbers... it would be very nice if anyone could help me! :) Thanks! (and sorry for mi english) ;)

[rosenred]

Excellent 'ible! If I may, I have a remark. The fact that I am somewhat clumsy, would certainly guarantee liquid spilled on the hot plate. So,  a way to protect the under side of the cpu, would be crucial in my case.

How about a piece of pcb (from an old hard drive or mb) cut in the size of the box, with a square hole in the middle for the cpu? It could be sealed with epoxy or even hot glue since the pcb of the cpu does not get that hot ;)

[Andy-K]

Would it damage the CPU if I tried to solder the + and - leads from the USB cable to the CPU. I think this would make a more reliable connection, but I'm not sure if the heat would damage anything in the CPU. Any advice would be greatly appreciated.

[TheFantastic]

all semiconductors have a "thermal budget" temp and time at temp are the critical factors. In the step of the manufacturing process I oversee wafers are routinely subjected to +1000c for up to 6 hours(silicon melts at ~1200c) to diffuse dopents and passivate the surface charges. the die size inside the chip package is very small, connected to the pins by gold(melts @ 1064c) wires.

Soldering even a good chip should cause no damage, though running it as a heater will eat up its thermal budget faster and will make it useless for anything else eventually.

[peanutthegreat]

CPU's are designed to run at darn near 80 degrees or more. If you're using an already dead one, and you do it quickly, it shouldn't be a problem.

[oli1122]

 Andy CPUs run at around 100C in most PCs and even in some over clocked servers at around 200C so solder wont damage it 

Olly :P

[mgysgthath]

CPUs (With an HSF) run between 25 and 50C ideally, if its any hotter you have a cooling issue. They WILL run acceptably up to 60-70C but after 75+ you run into problems, and after 80-90C the CPU will shut down to protect itself. Without a heatsink on the CPU, it will get hot enough to melt the socket it is sitting in, so it's probably sufficient to boil water.

[downgrade]

 Andy CPUs might run that hot, but I have never been able to get my hands on one.

All the CPUs I've ever have I have set to auto shut down at 65c, and I don't think I have ever had a computer shut down because of heat.

[Andy-K]

 Well that might be true with a CPU that is inside of a PC, which has all of the right features enabled for auto shutdown. However with a CPU that is being fed 5v straight from a USB port without any safety mechanisms, I bet it could get very very hot. The reason that a CPU inside of a desktop computer does not get near 100 degrees Celsius is because it is usually being fed a lower voltage. For example a CPU that is supposed to run at 1.5v will get very hot if you give it 5v.

[downgrade]

 Please don't post if you are just making things up.

Not even ram runs at 1.5v any more (well some does, but it's not common)

A full desktop lower power cpu runs at 3.65v usually. People who overclock sometimes get it up to, if not over 4v. My CPU runs at 3.8v and with just air cooling doesn't get over 50c.

Please sir, this is the kind of thing that ruins instructables.

[Andy-K]

I dont think you seem to understand. Maybe you should remember what it is I am trying to do here. I am PURPOSLEY trying to apply a larger amount of voltage to a DEAD cpu. This way it will produce heat, hopefully enough to be a good hot plate.

[downgrade]

You don't understand. What I was saying was a CPU is not supposed to run at 1.5v and that you were making that up. They are designed to run well over 3v, and most near (if not over) 100 watts (meaning, say at 3 vots thats 33amps max). I was also commenting on other people saying it's going to blow up and such (Andy CPUs was a joke pointing out his lack of punctuation). This will not make it explode. I am trying to say 5v is not all that much, especially 5v at a measly 500mA tops. (That's 2.5 watts, as compared to at least 65 watts a cpu will normally put out) 5v at 500mA will make some heat, but it's not going to be anything amazing or dangerous. Also, people have been soldering CPUs for ages. They used to do it to unlock the CPU to overclock it.

[Punkguyta]

 You're full of sh)t mate. Although a computer processor is rated for around 100-120C, they DO not run that fast. At 80C your average desktop processor will start to malfunction. I know this by accidentally leaving a cpu fan unplugged last time I cleaned a tower. Even if the fan is dustier than all hell, you shouldn't get hotter than 50-60C with a heatsink on it (even if theres no fan!)

Please don't mislead people that don't know the difference.

[ANDY!]

andy CPU's?

[hitokiri_808]

You never want your CPU to run over 70c load on a desktop or server, with under 60 being ideal.

Electrical solder melts under 200c btw.

[zoneykid]

Actually, I've found that most CPU's run at around half that in most PCs.(up to 80-90c max on load in a poorly ventilated computer) 100C+ would be dangerous to run at as it could damage the CPU.
Though i don't know about servers I'd assume the same.

[articice]

Servers run at much lower temps than workstations, because
- they have a decent (and noisy) passive ventilation system
- it's more stable
- it's much less power (the power dissipated increases as cube of temperature in silicon, if I'm not mistaken) and every watt counts in an enterprise-sized DC.

[Andy-K]

Thats what I was thinking, I have never seen a standard CPU get above 90 Celsius, and since soldering iron's put out much more heat than a CPU should put out, I am not still not so sure about soldering a CPU.

[khanguy]

No one in their right mind  would solder a perfectly good functioning CPU. The fact that it is already dead makes up for damaging the CPU. 

[GreenD]

 I'm wanting to make a variable hot plate - these cost 300+$ commercially.

I know by heating this above>200C you may desolder the board. But would a variable resistor be enough to change the temperature here?

[articice]

Nice idea, but you should have used all the pins and various voltages (to heat the entire thing, not just parts of it) and installed a current/temperature controller, possibly coupled with an active USB device - to get more current and to control the temp via a usb2serial interface or whatever.

[articice]

and, a wooden box may not pass some firefighting regulations or so LOL

[emilsegna]

What cpu are u using? P4 socket 478?

[pravardhan]

Hi,

CPU's work with low voltage. Older ones (upto Pentium 3) requires about 2volts. But, the newer ones (Core2's) require just about 1.7volts or even less.

And, there are special IC's that will provide with the proper voltage from the +12V supply...!

Bye,
PRAVARDHAN

[Shiftlock]

How hot does this get?  I can't imagine it gets very hot, considering CPUs draw 40+ watts, and the maximum current from a USB port is 500mW (1/2 watt).

[Marsh]

 Actually a USB port delivers 500 MilliAMPS, not mW. 500 milliamps at 5 volts is 2½ Watts. That's all a USB port can deliver. The CPU could however attempt to draw more than that. There's probably a current limiter built in to the port to prevent any damage though.

[jtmcdole]

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