Z820 RTX 30 card?

[cgmojoco]

I have the z820 product #LJ452AV

1125W Power Supply, dual Xeon

Wanting to know if I might be able to install a 3080 or 3090 successfully?

Right now I have a 1080ti successfully installed.

[Xgamerz]

take a look into that document 

z820 can support two 300w gpu's  + 75w of each pcie slot, total 750w !

if the gpu is under 375w, that mean u can use 300w + 75w from pcie slot, and i think that enough.

but there some other arround 400w TDP, in that case u have combine the pcie cables who can handle 600w + 75w of pcie slot to power up the 3090

[cgmojoco]

Thank you.

So has anyone had any success?  Do any of these RTX 30 cards even fit?  

[cgmojoco]

I forgot to mention, I already have 6pin to 8pin adapters .

(Startech brand​ - https://www.amazon.com/dp/B001TK3TJY/ref=cm_sw_em_r_mt_dp_H907QQJFH41BFM36H67R?_encoding=UTF8&psc=1) that I used for the 1080ti and the 1080ti works just fine.

I will be replacing the 1080ti with the 3090, hoping the adapters will work just fine on the G2 and G3 powerlines coming from the PSU.

[DGroves]

both of your listed videocard models are poor choices for a z820 graphics wise as even the fastest cpu's available for this model will not be able to keep up with the GPU's of the 38xx/39xx series

also, the 3080 is right at the limit of the z820 with the 1250 watt supply as the 3080 can draw 330 watts and the 3090 is a no go as it draws even more and is over the HP 330 total video card wattage limit

your current video card is the best match for gaming and overall general usage  unless you can make use of the 2080 TI's cores and new features