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G5 Space Heater
Posted by: aladds on 2022-12-06 04:32:31
The heating is struggling in my office today, and since it’s 3 degrees C outside there are lots of space heaters around the building to “top up” what the central system can’t manage (it’s being sorted).
Anyway I’ve had my old Quad 2.5Ghz G5 sitting under my desk waiting to be taken home for months now (I usually commute on the train and I’m not too keen to carry it under my arm!) so thanks to a few threads of “dd if=/dev/random of=/dev/null” it’s warming the area under my desk nicely 😊



4599C62F-7FC2-44FA-9BB1-5790AB224CFD.jpeg
Posted by: Phipli on 2022-12-06 05:29:42
Don't forget the graphics card! Time to install Boinc 🙂
Posted by: Sloar on 2022-12-06 08:48:29
Between my Quad G5 and Dual G5 the area around the desk is comfortable but the downside is that it attracts the cats.
Posted by: beachycove on 2022-12-06 13:20:09
A Quad at full load apparently consumes 0.455kw/hr. If we assume for argument’s sake that 100w of that is dissipated as heat (which I expect is an over-estimate, but whatever), you’d be talking about it providing 2.4kwh a day of heating. So maybe you could actually take the edge off the cold around your desk just by running a G5 Quad.

Let’s scale this up. One of those British always on cast iron cookers (Agas and such; there are several domestic brands) is said to warm a kitchen/ surrounding rooms by putting out anything from .7 to 3 kw/hr of background heat 24/7, depending on the model and the type of fuel. So if that’s right, then what you really need is somewhere between 7 and 30 Quad G5s running at full load to heat your office. Who said vintage tech was useless?!

Having said which, running 24/7 at full load, one Quad G5 would eat around $45 in electricity a month, and that’s at my measly $.14/kwhr rate, which is de rien in comparison to what the poor sods in Europe, California, and similar realms of darkness are paying just now. I will leave the multiplying by numbers 7 — 30 to your tender consideration.

Better get the regular heating system fixed, methinks!
Posted by: Krizzo on 2022-12-06 16:13:40
I'm currently working on my Quad as well, revamping the whole cooling system. For testing I'm doing the same. My house is well insulated and I basically don't need to heat it, only the occasional gaming or G5 testing session is enough to stay warm. I also use the computers to dry some underwear.
Posted by: 840quadra on 2022-12-12 19:15:21
I used to heat rooms with my dual G5 running Folding at home back in the day.
Posted by: Unknown_K on 2022-12-12 21:22:49
Never noticed my G5 DC PCIE model heating up my room much to be honest, but then again, I never ran it that long.

Now if I run my I7-980X with R9-280x graphics card long enough I do notice it in the summer. CPU is 130W TDP without overclock and the GPU is 250W.
Posted by: Phipli on 2022-12-12 22:40:34
If we assume for argument’s sake that 100w of that is dissipated as heat
Were does the rest of it go? You can't destroy energy. It all ends up as heat, unless you're sending it somewhere else as energy, like charging a battery or something.
Posted by: beachycove on 2022-12-13 04:13:27
Surely that .455kw would mainly be spent on spinning disks and fans, comparing numbers at a furious rate, and generally running the thing — generating heat as wastage in the process. How many watts would be wasted as heat is a guess, but the machine isn’t a simple resistor.
Posted by: Phipli on 2022-12-13 04:17:26
Surely that .455kw would mainly be spent on spinning disks and fans, comparing numbers at a furious rate, and generally running the thing — generating heat as wastage in the process. How many watts would be wasted as heat is a guess, but the machine isn’t a simple resistor.
All of the electrical energy ends up as heat eventually, unless it leaves the room somehow.

You can't create or destroy energy, and it isn't going anywhere else in particular. A good CPU does more computation for the amount of electricity it uses, it doesn't convert less of what it uses into heat - it is the end of the line, no where else for the energy to go. A CPU is a machine for turning electricity into heat, by thinking about numbers.
Posted by: Krizzo on 2022-12-13 13:44:42
From a purely physical standpoint all a computer does is to convert electrical energy into heat.
Posted by: Krizzo on 2022-12-13 14:03:19
Never noticed my G5 DC PCIE model heating up my room much to be honest, but then again, I never ran it that long.

Now if I run my I7-980X with R9-280x graphics card long enough I do notice it in the summer. CPU is 130W TDP without overclock and the GPU is 250W.
Well the G5 Quad CPUs have a TDP of 125 Watts – Each!
Plus the logic board uses up around 80 Watts as well. The whole system idles at around 220 Watts. If I let Unreal Tournament 2004 run with my Radeon X1900 GPU, the system gobbles 300 Watts which is half a toaster.
Posted by: Byrd on 2022-12-13 15:06:33
New gaming desktops use much greater watts now - 1200W PSUs very common - the G5 Quad doesn't seem so bad!
Posted by: Krizzo on 2022-12-13 16:18:24
It's better than I thought, but considering that a modern smartphone has the more computing power than a Quad...
Posted by: CC_333 on 2022-12-28 20:26:49
New gaming desktops use much greater watts now - 1200W PSUs very common
I remember hearing a few years ago that California banned the sale of certain computers from Alienware (and perhaps others) because they use too much energy for a given power rating or some other obscure reason.

c
Posted by: Unknown_K on 2022-12-28 21:55:44
I ran the i7-980x system a while today and I could feel the heat building up by my feet (130W CPU with some overclocking).

1200W power supplies are crazy, I don't have anything over 800W here and those are for old SLI/Crossfire setups.
Posted by: Phipli on 2022-12-29 01:51:47
I recommend buying a pass through kilowatt meter. Its interesting to wander about and see what different things use rather than their ratings. As an example, when I was buying my last PC, everything told me to buy a 500W PSU for my setup - I haven't seen it draw more thsn 200W at the plug.

Also, with energy prices, sometimes you discover that your 80s clock radio pulls so much power you could pay for a new one in 6 months, or a new fridge in two years. Its worth considering when energy savings pay for the kit.
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