How to actually build a great linux machine? Poor graphics performance

Question

I can't believe I am asking this question myself. I've been using linux since 1996, SuSE version 4.1...And yet I am still not able to put together a well performing machine.
I bought a simple box a few months ago. I am a software developer. I don't need high end graphics nor RAID nor stuff like that. My main goal is to have a fast responsive machine. I installed arch linux on it, and i3 as desktop environment - really it should be quite fast.
And yet...the machine responsiveness is very low, especially graphics lag A LOT. I know I didn't opt for a high end graphics engine - but shouldn't such a modern machine be enough for lag-free youtube and other video watching? Lag-free firefox browsing?
Maybe I just misconfigured my machine, and that's what my question is about. Some hardware info follows below. As you can see, I have a AMD E-350 processor with 8GB-RAM - I should think this would be quite enough for a standard linux installation...
What I also did is, as the MoBo comes with a GPU/processor bundle, I thought that maybe upgrading just the graphics card may have some impact - nope. I bought a AMD HD5450 card with 1GB RAM (!!!) - and still I can't enjoy a fluent video on youtube, nor a sufficient experience web browsing...(maybe it's even better to have the original GPU than the added card I bought?). Of course I know that modern browsers are pretty demanding, but I should think such a machine should be able to handle it?
I read the posts on the arch linux forum about optimizing video, and AMD cards are not very well reviewed really...
There are infinite sites about how to choose your distro, there are hardware compatibility lists - but are there any tutorials or guides which actually help setting up a fast and responsive machine?
* Is my machine maybe badly configured?
* Does it just have a bad hardware set up? Should I maybe replace one or the other piece to cheaply get satisfactory performance?
* Am I just asking too much from my cheap hardware?
I am considering replacing the whole MoBo (I know it was cheap and I shouldn't expect too much from it, but I thought I should be able to tweak it...)
(lshw):
*-memory
description: System memory
physical id: 0
size: 7967MiB
*-cpu
product: AMD E-350 Processor
vendor: Advanced Micro Devices [AMD]
physical id: 1
bus info: cpu@0
size: 800MHz
capacity: 800MHz
width: 64 bits
capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp x86-64 constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf pni monitor ssse3 cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch ibs skinit wdt arat hw_pstate npt lbrv svm_lock nrip_save pausefilter vmmcall cpufreq
*-pci:0
description: Host bridge
product: Family 14h Processor Root Complex
vendor: Advanced Micro Devices, Inc. [AMD]
physical id: 100
bus info: pci@0000:00:00.0
version: 00
width: 32 bits
clock: 66MHz
configuration: latency=32
*-pci:0
description: PCI bridge
product: Family 14h Processor Root Port
vendor: Advanced Micro Devices, Inc. [AMD]
physical id: 4
bus info: pci@0000:00:04.0
version: 00

Answer 1

If I am not mistaken, the E-350 is equivalent to the Intel Atom D525. I have the D525 and use it in my media center. It performs very well at one task at a time, but dies a horrible death under multi tasking situations like a desktop. I blame browsers. I have a top-end laptop with the second fastest mobile i7 I could buy (in Dec 2014), a Geforce GTX 970m, that shares 6GiB VRAM with the intel 3D chip, and on top of all that 32GiB quality RAM with reasonable latencies. I'd really like to brag, because the thing was insanely expensive, but there are no grounds for bragging. When I open a browser, I still feel like it's 2004, everything is sluggish and slow and websites become more full of crap every day, everything is big and blaoted. The desktop, no matter which one, does not feel the least bit snappier than it used to ten years ago, although the processing power has multiplied. Desktops now have more crappy features, more "connectivity", more need to do everything. The immense availability of fast hardware and fast networks in metropolis of metropolis centered countries creates the illusion of an abundance of everything. And now I'm sitting here and all I want is a low power low cost machine to do every day tasks. While the industry is going on and on about the internet of things, I still wait for the day the internet of people happens.
It's not you. It's like interface designers are trying to mock us. Instead of snappy technology on snappy hardware with snappy code and a snappy workflow, we get "our interface is based on common technologies like HTML and CSS" in the ads for a static local operating system. Nothing ever works. We just had arrived at the following points in tech development:
- Gnome probably had every possible feature on the planet, that made a desktop useful, there were plugins for everything, a setting, a switch.
- Web sites on big screens finally became versatile, feature rich and less static.
- Desktops generally performed very well. Click-Action without a delay.
Then the following happened:
- Gnome 3, new desktop concept, rewrite, all the plugins are gone, I have to re-learn everything from the scratch and, since it was new, I have to re-arrange my workflow.
- Now we are supposed to look at the internet through a <5" screen. If feels like 2001 again, browsers suck, where are my addons, my plugins, my customization?
- Desktops use simple languages, that swallow performance like a maniac.
Of course you cannot really buy classic stuff the way it was, because the consumer marked is trend based, not centered around ergonomics. Another five years from now on:
- Gnome 3 has all the good features and works well for everybody, because there are plugins, custom interfaces and whatnot. But it has to be replaced by Gnome 4, because it does not work well with tactile feedback and bowel movement based controls. Adapting the old system is not possible, let's do it again.
- Mobile browsers are finally comfortable, but we are not supposed to look at the internet at all anymore, information has been simplified to the point, where it is sufficient to put small plugs into our orifices to be informed about everything important by short bursts of vibration and temperature change.
- Desktops had a chance to catch up with the inefficiency of a "if it's not interpreted or byte code, then I don't want it" mentality, but now everything has to be in 3D, projected on thin air with a multi trillion cubic voxel resolution. And everything is slow again.