Intel Core i5 6402P - RM 707
Gigabyte H110M-DS2 (D4) - RM 276
Kingston 8GB DDR4 2133MHz Value RAM - RM 145
Palit GTX950 2GB GDDR5 StormX - RM 609
WD Blue 1TB HDD - RM 209
Corsair VS450 - RM 162
TP-LINK TL-WN722N USB WiFi - RM 45
Tecware F3 - RM 125
BenQ GW2470H - RM 469
Total: RM 2747 (ETech price inclusive of GST)
Optional upgrade:
1. 240GB SSD (or 120GB if only for OS)
2. 16GB RAM (if you deal with many large Excel files)
3. PCIe based WiFi adapter for better stability
4. IPS monitor
5. Other case (your own preferences)
WiFi is prone to interference, obstacles and many external factors, for optimum connection experience, you are recommended to use ethernet cable.
You can swap to a mobo with onboard WiFi card like Gigabyte H170N-WiFi, but that would cost RM 200+ more.
As for USB dongle, any cheap TP-LINK will do if you are still using single band router (2.4GHz) only, it makes no difference to get dual band when you are being limited by the router itself

Is that like the kind of spec that "maxing out" on Dota2? i.e. should I upgrade the CPU or GPU for a better performance? And what do you mean 120GB for SSD if only for OS?
Sorry for being such a noob. I've only used laptops so far. First time building my own rig.