9700X is meant to be the best cpu for photoshop. beats the 9950x and core ultra 9 285k, and can be had for £273 with a quick searchBudget - £500 - can stretch if needed.
Usage - Work machine. Web dev, Photoshop. Maybe the odd bit of gaming
Looking at: CPU/Mobo/RAM/Cooler (GFX possibly - I know that will bump the cost though!)

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mobo has spidf that you wanted..otherwise you can go cheaper...but also gives you a future upgrade path..think any new intel cpu will require a new mobo now
My basket at OcUK:
- 1 x MSI B850 GAMING PLUS WIFI (AMD AM5) B850 ATX Motherboard (SKU: MOT-MSI-03994) = £179.99
- 1 x Corsair Vengeance EXPO/XMP 32GB (2X16GB) DDR5 PC5-48000C36 6000MHz Dual Channel Kit (SKU: MEM-CRS-00996) = £79.99
- 1 x Arctic Freezer 36 120m Black CPU Cooler - 2x 120mm (SKU: COO-ARC-02420) = £22.99
Total: £282.97 (includes delivery: £0.00)
SAVE 5%

MOT-MSI-03994
£190
(incl. VAT)
£180
(incl. VAT)
FREE DELIVERY
SAVE 29%

£140
(incl. VAT)
£100
(incl. VAT)