How powerful a CPU do I need?

[clv101]

I haven't bought a desktop CPU or system for 13 years. Not since my Core 2 Duo E4300 1.8GHz, overclocked to 3.2GHz. For the last decade I've been exclusively running MacBook Pros and in the last few months a ChromeBook. I'm now in the market for a modest, low power consumption desktop but unclear exactly where to dive in. The CPU world seems a lot more complex than it used to be!

My personal points of reference are few, looking at cpubenchmark.net:

My old E4300 (similar to an E6850) 65W single thread rating 1187, CPU Mark 1124
My 2012 MPB has the i7-3615QM 45W single thread rating 1680, CPU Mark 5030

I'm initially drawn to the Ryzen 7 4800U 15W single thread rating, 2633, CPU Mark 17546.

The Ryzen looks good compared to what I'm used to. Much more performance for a lot less energy. What's the catch? It even seems to have half decent graphics built in. I'm quite tempted by the recently announced Asus PN50, seems like a tiny box with great performance - just no opportunity for external GPU.

Questions:
How capable is the 4800U's GPU? Can it actually cope with modern games at 1080p?
Is it possible to buy a Ryzen 7 4800U system with potential to add a PCIe GPU?
What's the advantage in going up to the 65W desktop processors with all their extra heat, energy, size and noise?

I think what I really want is very small desktop based around the 4800U with a single slot for an external GPU, does such a thing exist?

Should add, this will be a Windows 10 'family' PC. Used for web, office, photo editing, streaming and (potentially) light gaming.

 

[DarkMatter]

Questions:
How capable is the 4800U's GPU? Can it actually cope with modern games at 1080p?
From my experience of using a 2400g (20% or so slower than the 4800U I believe) its doable if you are not picky. Set everything to the lowest it can go for 1080p for most modern games and they do run but at 20-30fps. I play a lot of older games and it was perfectly good for that.

Is it possible to buy a Ryzen 7 4800U system with potential to add a PCIe GPU?
No the 4800U is a notebook CPU so baring using an external thunderbolt GPU solution. The desktop version of the 4800U, the 4700G (i think) is meant to be out soon but no official date has been given, this would allow the use of a GPU but in a much larger case than the asus PN50.

What's the advantage in going up to the 65W desktop processors with all their extra heat, energy, size and noise?
Notebook CPUs from my experience have much lower base clocks, if one core is stressed it will boost high but if all cores are stressed it will have a much lower clock than the desktop chip. If you don't need all the processing power then they are not worth the extra heat/size/noise.

I personally think devices like the PN50 make great family computers and the integrated graphics are good enough (my wife uses one fine) and offer great value for money. I also use a Asrock Deskmini as a secondary PC which is great.

 

[eeek]

@DarkMatter there are going to be mini PCs using the Ryzen 4000 u laptop chips because they offer an interesting option compared to Intel equivalents see https://liliputing.com/2020/07/asus-pn50-is-a-mini-pc-with-up-to-an-amd-ryzen-7-4800u-processor.html which @clv101 mentions

What I will say is that those mini PCs are targeting a particular market and so are neither cheap nor that expandable as that isn't what the market wants. Nor is it worthwhile trying to create expandable versions as the chips are designed for direct soldering on to the motherboard which means that adding pci-e sockets is both serious additional work aimed at a stupidly small audience.

Now in the intel world the solution for expansion was is to use thunderbolt with an external GPU box but Ryzen doesn't support thunderbolt so that isn't an option - not that I would recommend going down that line as it rarely worked on any of the 3 laptops I tried that approach with before I gave up in disgust and built a desktop for work and gaming.

My suggestion would be to look at the ryzen 3600 (but you will need a gpu) or the new APU 4650G / 4650GE (low energy) chips when they (if) become available in an itx case that is big enough for the graphics card you want. My 3800x only consumes 20 watts unless I throw something really complex at it and I suspect the 3600 would consume significantly less and the recently announced 4650G will be the same.
https://www.techradar.com/news/amd-...leaked-online-listing-suggest-imminent-launch

 

[CuriousTomCat]

The Ryzen looks good compared to what I'm used to. Much more performance for a lot less energy. What's the catch?

You've discovered that modern technology uses less energy than old technology and you're asking where the catch is? Literally EVERYTHING uses less energy in 2020. Fridge freezers, TVs, washing machines, dishwashers, cars etc are becoming more enrgy efficient, hense the A, A+, A++ and A+++ energy ratings you see everywhere. There's no catch, it's genuine progress.

The Ryzen 7 4800U is an excellent CPU.

How capable is the 4800U's GPU? Can it actually cope with modern games at 1080p?
Is it possible to buy a Ryzen 7 4800U system with potential to add a PCIe GPU?
What's the advantage in going up to the 65W desktop processors with all their extra heat, energy, size and noise?

I think what I really want is very small desktop based around the 4800U with a single slot for an external GPU, does such a thing exist?

Should add, this will be a Windows 10 'family' PC. Used for web, office, photo editing, streaming and (potentially) light gaming.

The 4800U is a laptop CPU. One of the reasons it uses less energy than it's 3800X desktop big brother is because it's got lower clockspeeds:

4800U - 1.8GHz base and 4.2GHz boost
3800X - 4.9GHz base and 4.5GHz boost

If you want a desktop gaming PC, please, stick to desktop CPU's because that's what they're designed for.

 

[Tetras]

For 1080p gaming you really need a minimum of a RX 570/580, the 4000 series APUs can do it, but like said above, this is with everything on low. If you're willing to stick with old games, especially DirectX 9, then it is more realistic.

It sounds like you want an ITX PC.

 

[clv101]

For 1080p gaming you really need a minimum of a RX 570/580, the 4000 series APUs can do it, but like said above, this is with everything on low. If you're willing to stick with old games, especially DirectX 9, then it is more realistic.

It sounds like you want an ITX PC.

Yes, that's a good point. If I want more graphics performance than the 4000 series APUs I need an external card. That leaves me thinking, that if I'm going down the external GPU route, do the new Ryzen 7 APUs still make sense? Would I be better off without the integrated GPU?

What does the external GPU do to power consumption - when just on the web for example, not gaming? Do they have a large power consumption overhead compared to integrated GPUs?

I'm liking the idea of the recently announced Ryzen 7 4700GE, ups the TDP to 35W in exchange for higher frequencies. It sounds like these new Ryzen 7 chips are only going to be available to OEM system builders like Lenovo and HP initially though. I'm probably okay with that though, the Lenovo ThinkCenter M75s looks like a nice machine. A bit more potential compared to something like the Asus PN50 4800U machine.

 

[Tetras]

Power consumption: it's difficult to say without seeing a desktop 4000 APU reviewed, but ITX Ryzen APU builds have been around 20 - 40 watts, there's a pretty large variance between different builds and motherboards. An RX 550 or GT 1030 uses around 3-5 watts idle with fan switched off, a 1650 or 5500 is around 5, RX 570/580 it seems to depend on the hardware/BIOS cos I've seen anywhere from 8 to 25.

It's not the whole story though because the CPU and motherboard can be impacted by using a dGPU too, so if you said a 10 watt increase at idle for a modern GPU (not high-end) then that's a safe assumption.

The APUs are unlikely to make sense from a price/performance perspective (if you're not using the IGP), but I've seen only euro prices. Their power consumption will be a fair bit lower though, especially the mobile ones.

I don't think the TDP limitation is worth it cos you can easily downclock other Ryzens and you'll suffer the same cooling issues for photos and editing if you have a compact case with a mobile CPU.

Low clocks don't automatically mean more efficient either, especially with duration-based workloads like photo editing. They may also impact the smoothness of gaming while you're streaming.

Your usage doesn't sound well suited to an APU, as things stand, depending on the balance of those workloads and the intensity of the gaming, not until APUs take a leap forward in 1080p gaming performance.

 

[Poneros]

igpu performance, check the channel for more

 

[Jacky60]

Have you considered going Atom or maybe micro tablet/USB 3.0 PC? Literally a bare bones minimalist stripped down system sounds like it would suit. There are super small form factors that may well be better suited to your needs and wants than a hefty Micro ATX. I'd defo consider the USB 3.0 stick PCs unless you really feel you need more GPU grunt. Incredibly low power and footprint!

 

[Uriel]

Options for Ryzen systems with external GPUs are limited because they usually lack thunderbolt 3, an Intel technology. There are some motherboards that support it but not many.

 

[Deleted member 209350]

If you are looking for a desktop, Im not sure why you are looking for laptop CPU's?

Something like a Ryzen 5 3600 has more than enough power to last you years and its pretty cheap as well. If you want a CPU with integrated graphics I would suggest one of the new Renoir APU's like a 4600G

 

[clv101]

I'm keen to get the power consumption down as low as possible (house is off-grid, 100% self sufficient in energy).

 

[sandys]

How capable is the 4800U's GPU? Can it actually cope with modern games at 1080p?

It will be good enough for most things if you have modest requirements, I run a 2400G and I can play a lot of titles at 1080p med/high settings around 30fps, so current console quality. Have you tried game streaming on your chromebook?

Is it possible to buy a Ryzen 7 4800U system with potential to add a PCIe GPU?

At the moment these aren't yet out for you to buy for desktop but will be soon at which point you could build a system that can take any GPU in the future but sounds like yuou have modest needs so you may never need a GPU.

What's the advantage in going up to the 65W desktop processors with all their extra heat, energy, size and noise?

Allows it to maintain higher clocks on CPU/GPU when you need it, when you don't modern CPUs and GPUs are very efficient and won't use anything near that level of power.

As mentioned by others an ITX build might be your best choice in that you could be ready for an upgrade if needed, alternatively you could buy a gaming laptop with an Intel CPU and decent GPU and provided it has thunderbolt it that would give you GPU options in the future.

All comes down to budget and what you really want/need out of the system.

 

[jigger]

The 4700GE looks like it’s a 30watt part offering around the performance of around a 130-140watt desktop system with dedicated graphics. The U processors are 15watt parts for the note/ultra books market so any desktop system would probably need to be a SSF design.

 

[nomadd]

I'm keen to get the power consumption down as low as possible (house is off-grid, 100% self sufficient in energy).

Then you are probably aware that the monitor will be consuming 30-60W depending on the model.

Based on your requirements listed above (office, web and light gaming), then just buy a thin and light laptop. Plenty of AMD ones around with more than enough performance.

 

[clv101]

Indeed, and we've been exclusively laptops for a decade. The stimulus for this is to have a fixed 'family computer' for children to use. Not too keen on the 5 yr old having free use my MBP!

 

[PhoenixUK]

https://shadow.tech/ ?

 

[sandys]

Indeed, and we've been exclusively laptops for a decade. The stimulus for this is to have a fixed 'family computer' for children to use. Not too keen on the 5 yr old having free use my MBP!

Then an APU will suffice even last gen is fine, whilst the 4xxx series will use less power for equal config which is your key focus it looks like they are pairing the big GPU (which is what you want really) with a pointlessly big CPU which will likely consume more than you need in use, so you may actually be better off with a 3400G as lets face it when APU gaming the CPU is never the bottleneck and the 4c/8t is still plenty capable should you drop a better GPU in the future.

I have no backup for the power statement, so you'll have to do a bit of research on that score as my assumptions that a 4c/8t 12nm APU will use less than a 8c/16t 7nm APU could be garbage.

Looks like the 4700GE has a lower power CPU with the full GPU, that could be a winner but is OEM only, whether it will tip up in prebuilt stuff like overclockers or other mini itx builders when it is available who knows.

 

[Cyber-Mav]

Used a android media player that runs full android cost 40 quid. Plays all videos youtube, office app, web browser etc. Good enough for cheap computing. Being android no headache with windows windows.
Somone should turn android into a proper desktop os. Would be good. Phoenix os and remix os were ok but needed more work.

 

[BluesFanUK]

Used a android media player that runs full android cost 40 quid. Plays all videos youtube, office app, web browser etc. Good enough for cheap computing. Being android no headache with windows windows.
Somone should turn android into a proper desktop os. Would be good. Phoenix os and remix os were ok but needed more work.

I experienced the opposite with a Windows one, an AWOW Gemini Lake mini PC. Awful product that was supposed to be 4K ready. Not sure if I had a faulty unit but 4K stuttered and I got so many BSOD's trying to update the iGPU I had to return it. I'll never trust those small HTPC machines again.