I disagree with this statement completely. I've been following the GPU landscape for close to 15 years and I've noticed that the low powered videocards with good perf/watt tend to have large premiums and generally poor/awful performance/$. That means saving $30-50 on a high quality PSU actually ends up costing MORE long-term in terms of GPU upgrades. Cards such as GTX750/750Ti/950/960 all come to mind that had excellent performance/watt but horrible price/performance compared to much faster card that required a solid 500-550W PSU unit.
There have been so many deals on good PSUs over the years in the US, that there is 0, and I repeat 0 excuses why someone should sacrifice the choice of what CPU/GPU they can buy over the next 5-10 years to save what $20-50? Saving on the PSU is literally THE worst thing any new PC builder can do long-term. The PSU is the most important component in a system and money should first be saved on the motherboard, case, memory or just about anywhere else, not the PSU.
There is no reason a budget build cannot include a good PSU that can power any single GPU on the market. Some deals in the past:
XFX TS Series 750W Quiet ATX 80 Plus Bronze Certified Power Supply (P1-750S-NLB9) 5 Years Warranty $35 ( MIR $35)
750W Thermaltake Toughpower 80+ Gold Modular Power Supply (PS-TPD-0750MPCGUS-1) for $79.99 -
$25 Rebate =
$54.99.
EVGA 600W 80+ Certified ATX Power Supply (100-W1-0600-K1) on sale for
$29.99.
700 Watt EVGA 700B 80 Plus Bronze Certified Power Supply (100-B1-0700-K1) [newegg.com]
The PSU also allows overclocking headroom and stability for both the CPU/GPU and upgrade path to more powerful 6-10 core CPUs. Furthermore, gamers who are just entering the PC gaming scene could eventually choose to move away from 6/8-pin videocards towards 200-250W GPU class of flagship cards. This is especially true as 3440x1440, 4K, 1440p 144-200Hz, etc. start to gain traction over the next 5 years.
I've been on the forums for so long that I can say without a shadow of a doubt any PC build with a budget/lower end PSU is an incorrectly build PC system. Any small amount of $$$ saved to meet some arbitrary budget will end up costing a lot more in the future.