Studio XPS 7100, PSU replacement?

What's wrong with the one you have?

I see some used/refurbished Dell PSUs for the Studio XPS 7100. And it seems the Studio XPS 7100 and Vostro 400 can use the same PSU, so that might be another search option..

It started running roughly and then died altogether right after I gave it to my son. Won't power on now. I found a couple priced around $45 - $50. But I don't know whether or not to trust the site. Especially on a refurbished item. I saw others that I thought were too much for a refurbished part. Thanks for the suggestion. 

There is nothing special about 7100 psu.  Any standard MT form factor Dell or reputable non-Dell ATX psu with 24 pin ATX 4 pin cpu that is at least 460 w will do.  
priced around $45 - $50 is too much for a used psu. $20-25 or lower is better.  
E.g., any Dell XPS 8300/8500/8700 psu will do.

this one on eBay is $29 and you may bargain for a lower price.

7100 has limited lifespan left in this era, unless you want to keep it running indefinitely no need to buy a new psu.

https://www.amazon.com/Genuine-Dell-Systems-Compatible-Numbers/dp/B009F09ASY

Genuine Dell 460W 7YC7C 8FC6W DGX9R Power Supply
For The Studio XPS 7100, and Vostro 400 Systems Dell Compatible Part Numbers :
DGX9R, 8FC6W, 7YC7C Dell Compatible Model Numbers: DPS-460DB-4 A, ATX0460AWWB, PC9004

I would recommend this as replacement

https://www.bestbuy.com/site/evga-br-series-700w-atx12v-eps12v-80-plus-power-supply-dc-dc-technology-black/6346160.p?skuId=6346160

https://www.evga.com/products/product.aspx?pn=100-BR-0700-K1

The PSU is NOT ATX12V from 1995 its EPS12v PFC 80 percent efficient with at least 142W combined on the 3.3v/5v rails.

Even Dell 305w units meet that spec. Power supplies have several rails and a single spec of watts is not sufficient for a replacement. Several vendors only have 90 to 130w combined for these rails even with their 1000w units.

Thanks for the replies. I just wanted to make sure the one I got had all the wires, and they were long enough to reach the plugs. That's why I only concentrated on the exact model. And I thought I needed one that didn't have any extra switches or anything that I don't have cutouts for.

Will this one work ?

https://www.ebay.com/itm/321332646882?ul_noapp=true