A GT 1030 should consume around 35W under Furmark.
Nvidia GeForce GT 1030 2GB Review
Nvidia's tiny GeForce GT 1030 is cheaper, smaller, and cooler-running than AMD's Radeon RX 550. But can it compete in our benchmark suite?www.tomshardware.com
It's not 25W but @GuilleAcoustic was able to run it successfully from a 4X slot (using the same Asus Q87 MB).
In my case, I use my custom riser with 12V tracks cut : the Polulu board provides all the power needed, nothing comes from the MB slot.
Also, my motherboard has a 16X slot
Exactly, been running GT1030 on my Asus Q87T for quite a long time without issue. I was using a 35W i7-4785T and some 90W Dell brick 19.5V or so, but their's a tolerance on the DC voltage you provide (10% if I remember correctly).
I asked Asus directly and they replied I should be fine since I wasn't running the max TDP allowed on the CPU side.
Thank you both, that makes for interesting reading and potential to use my Q87T.
It has an i3 4130 in at the moment, so that may be fine compared to an i5 for example.
My newest build which is in dire need of documentation is v0.9 at the moment and seems to work fine in its crammed in just for testing phase.
I bought a used H81N / i3 4130 / 8GB bundle on ebay, and intend to put an i5 in as soon as it's all properly tested. The 4130 can go in my underpowered H81T that has no PCIe slot at all.
The v0.9 build is also running a modded GTX 1050Ti from @Goatee which has a passive heat sink on it as standard. Adding an 80mm Noctua Redux seems to be keeping it reasonably cool.