SSDs always fragment because of how they work.
HDDs are terrible for random reads/writes so you want all files to be as continuous as possible or performance will suffer.
The whole point of SSDs is that they are good at random reads/writes (no moving parts) so fragmentation doesn't really matter.

So basically defragging HDDs:
pro: gets faster
con: none
Defragging SSDs:
pro: none
con: dies

Included with both CPUs.
FYI you might have to update the BIOS on the AMD build. If you're buying it from a retailer you could ask them to do it otherwise https://support.amd.com/en-us/kb-articles/Pages/2Gen-Ryzen-AM4-System-Bootup.aspx

You can just change that in your settings anytime though.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel - Core i3-8100 3.6GHz Quad-Core Processor (£91.14 @ Aria PC)
Motherboard: ASRock - Z370M Pro4 Micro ATX LGA1151 Motherboard (£99.84 @ More Computers)
Memory: Corsair - Vengeance LPX 16GB (2 x 8GB) DDR4-3000 Memory (£169.00 @ Amazon UK)
Storage: Samsung - 850 EVO-Series 250GB 2.5" Solid State Drive (£81.54 @ Novatech)
Storage: Seagate - BarraCuda 1TB 3.5" 7200RPM Internal Hard Drive (£33.95 @ Aria PC)
Video Card: MSI - GeForce GTX 1050 Ti 4GB Video Card (£157.20 @ Amazon UK)
Case: Cooler Master - N200 MicroATX Mini Tower Case (£46.74 @ Amazon UK)
Power Supply: Corsair - CXM (2015) 450W 80+ Bronze Certified Semi-Modular ATX Power Supply (£48.86 @ Ebuyer)
Total: £728.27
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-03-24 21:13 GMT+0000

Should get an 860 Evo 250GB but that's not listed on pcp UK for some reason.
You can get a different case if you want.
An i3-8350K would be a bit faster and overclockable but you'd need a cooler and even without that it wouldn't be within the budget anymore.

AMD option, slightly worse <=4 threads (most games), better for >4 threads (in your case only photoshop and even then not all the time):
PCPartPicker part list / Price breakdown by merchant

CPU: AMD - Ryzen 5 2400G 3.6GHz Quad-Core Processor (£129.59 @ Aria PC)
Motherboard: ASRock - AB350M Pro4 Micro ATX AM4 Motherboard (£69.38 @ More Computers)
Memory: Corsair - Vengeance LPX 16GB (2 x 8GB) DDR4-3000 Memory (£169.00 @ Amazon UK)
Storage: Samsung - 850 EVO-Series 250GB 2.5" Solid State Drive (£81.54 @ Novatech)
Storage: Seagate - BarraCuda 1TB 3.5" 7200RPM Internal Hard Drive (£33.95 @ Aria PC)
Video Card: MSI - GeForce GTX 1050 Ti 4GB Video Card (£157.20 @ Amazon UK)
Case: Cooler Master - N200 MicroATX Mini Tower Case (£46.74 @ Amazon UK)
Power Supply: Corsair - CXM (2015) 450W 80+ Bronze Certified Semi-Modular ATX Power Supply (£48.86 @ Ebuyer)
Total: £736.26
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-03-24 21:20 GMT+0000

#2819
Well what are your needs?
And with fans you mean the CPU cooler?

#2820
Flag says USA "£750" says not USA.
How much storage capacity will you need? <250GB, <500GB or >500GB?

Not really.
Is the mobo a random pick or specific reasons for that one?
Case is your choice.
750W is a bit overkill but aftermarket 1080 Ti + oc'd 8700K will go quite a bit above TDP so 550W might not be ideal either but there are no cheaper equivalent 600/650W PSUs on pcp right now. Maybe https://au.pcpartpicker.com/product/WrNypg/seasonic-focus-plus-gold-650w-80-gold-certified-fully-modular-atx-power-supply-ssr-650fx for 1$ more but nothing actually cheaper.

Onboard sound is shit for microphones. If it's a USB microphone then the mobo doesn't matter and you're just bad at installing drivers. Or Windows 10 is fucking them up for you.

You should reinstall or at least you'll have to reactivate windows (different mobo) but you can reuse both the SSD and HDD. If you get a new SSD then 860 Evo.

Very a very relative term.

No. I mean what do you think those 3 fans on the GPU do?
Fuck Aio liquid coolers for CPUs though.
http://www.teamfortress.tv/12714/pc-build-thread/?page=19#557

You could afford a 1050 Ti.

Well no one is going to leave a review "the mobo was not DOA". DOAs happen.

Do you mean those complaining about the VGA and HDMI output not working with a CPU without an iGPU, those who can't change the BIOS settings because they don't know which key to press or those complaining that motherboards manufactured before the 2400G was released don't have a BIOS version installed that supports while refusing to update it themselves?
FYI https://support.amd.com/en-us/kb-articles/Pages/2Gen-Ryzen-AM4-System-Bootup.aspx

Yes. Not sure what 2xxx will bring but the 1500X might drop in price or there might be a higher clocked CPU at the same price.

Depends on the price obviously and it's only interesting because you can afford a discrete GPU.

Hopefully yes, unless mining bullshit happens again.

Yes, what exactly is the question you are trying to ask?

#2808
Mini ITX is usually more trouble than it's worth.
Micro ATX with 4 RAM slots, so you can just add 2x4GB instead of having to buy 2x8GB and not being able to use the old RAM anymore, B350 so you can overclock later should you change your mind (also A320 is low end).
You could afford 16GB if you wanted it, but RAM prices should drop later this year so better to wait and only upgrade should you have to.
I'd add an SSD.
You could afford a CPU if you wanted.

You'll have to update the BIOS somehow to get the 2400G to run though. An X470 would be more expensive and B450 won't be released until later this year.
On that note not only X470 is coming (April iirc) but also the rest of the Ryzen 2xxx lineup. No iGPUs but the 2600 or something like that might be interesting regardless. Or simply the 1500X if it drops in price. Since you could afford a GPU it would be an option. Depends on when you want to buy it.

2400G + updating the BIOS somehow is fine too though.
PCPartPicker part list / Price breakdown by merchant

CPU: AMD - Ryzen 5 2400G 3.6GHz Quad-Core Processor ($167.21 @ OutletPC)
Motherboard: Gigabyte - GA-AB350M-Gaming 3 Micro ATX AM4 Motherboard ($72.89 @ OutletPC)
Memory: G.Skill - Ripjaws V Series 8GB (2 x 4GB) DDR4-3200 Memory ($103.89 @ OutletPC)
Storage: Samsung - 860 Evo 250GB 2.5" Solid State Drive ($94.99 @ Amazon)
Storage: Seagate - BarraCuda 1TB 3.5" 7200RPM Internal Hard Drive ($44.28 @ Amazon)
Case: Cooler Master - MasterBox Lite 3.1 MicroATX Mid Tower Case ($29.99 @ Newegg)
Power Supply: Corsair - CXM (2015) 450W 80+ Bronze Certified Semi-Modular ATX Power Supply ($26.99 @ Newegg)
Total: $540.24
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-03-19 11:40 EDT-0400

Dress code.
No fun allowed.

EDIT: Just in case you didn't know: Blizzard tried to permaban everyone in twitch chat who used the TriHard emote because they decided that using it is now considered racism. They eventually gave up.

I just want him to get downfragged harder.

Also because anyone who ever looked at the tables would know that it's called Premiership not premium. This isn't a saigns server.

Neither, wait and see.
If B360/H370 mobos become available get that and an i3-8100 instead, cheaper and as fast as the i5-7500.
If the 2400G becomes available get that, same price as the 1400 but faster and with an iGPU.

Only if both or neither become available then you have to choose.
Otherwise it's obvious. 7500/8100/2400G are faster than the 1400 but the 7500 is more expensive.
With a B360/H370 mobo the 8100 is cheaper than the 7500 and faster than the 1400 (same price). No reason to get the 1400 anymore.
Same reason with the 2400G. Cheaper than the 7500 and faster than the 1400.

Also it doesn't matter if some people aren't ok with AMD, unless you're one of those people.

EDIT: The 2400G is available you just can't select it because no mobos are available yet. The B350 mobo would work but you'd have to somehow update the BIOS.
Also it's 30€ more expensive than the 1400 atm.
Just wait and see.

Ok.
Yes as in you want to overclock or as in you're willing to do it?

You can't really afford Coffe Lake + overclocking so your options are Kaby Lake (7xxx) and no overclocking, Coffee Lake and no overlocking if B/H mobos show up in time or AMD Ryzen and overclocking.
https://www.topachat.com/pages/configomatic.php?c=i8QWApVFTH6MGahft1UzMpHvtfZ9luYrZ1vIKNl%2BXNU%3D
https://www.topachat.com/pages/configomatic.php?c=naIUxtNUA4cGCCEAXqgzdelTAOzhfI5IgBObuDWuB94%3D

An i3-8100 + B/H mobo or Ryzen 2xxx (e.g. 2400G) are going to be cheaper/better at the same price so if you're lucky those will show up in time.
Also don't get a mobo with only 2 RAM slots when you're already going with only 8GB to stay within budget. You'll regret it when you want to ugprade. I'd also get an SSD.

Overclock yes/no?
Streaming yes/no?
When are you going to build it?
Same shop?