In dire need of assistance with customizing a prebuilt workstation(HP Z220)

[yahyahayabusa]

I'm embarrassed to share this story, but maybe it's best I seek assistance.

I first saw this build on reddit:
https://www.reddit.com/r/buildapc/comments/7y5fi6/175_computer_gaming_build/

I plan to do CAD and Xcode(swift) with this pc, so I thought I'd get me a quad-core Xeon processor instead of the Core line to have the ECC support, and throw in a 750 Ti for gaming.
So I purchased a prebuilt HP z220 SFF(Small Form Factor) workstation. As I was purchasing it, I realized that a regular sized GPU could not fit, the seller told me you could just bend the frame to fit it...I thought I really wanted this Xeon cpu, so I'll make do, wasn't worried about aesthetics.
Everything was exciting and going well, until I tried running CS:GO on my ancient GPU from a previous pc my friend had built me years ago just to see how it ran. The game crashed at map loading and blue screen saying insufficient power. I looked up the power requirement for the 750Ti since this was the card I plan to buy, and found it required 400W.
Here's where we get into the issue. This workstation uses a 240W specific small sized power supply unit, which a regular PSU wouldn't fit inside the case, which I didn't care, I thought I'd put the PSU on it's side and leave the top of the case open. So I went and purchased a 500W power supply, the next issue came up. The PSU's on the market come with a 4pin cable, and this motherboard takes in only 3 cables from the PSU: One 2x2 for CPU, one 2x3 for main power, and this specific 1x6 pin for "power COMM". The PSU I bought only has a 4 pin. I asked the guys at canada computers whether they had anything to fit, they said no, it's a specific pin and nothing they sold was compatible. Sooo. I'm just lost in ways to solve this problem.
Should I purchase the pc recommended in the reddit thread and just replace the cpu and ram with the ECC I have in my current one?
Or is there a way to get my hands on a 1x4 to 1x6 pin converter or some power supply that offers it. I've tried almost everything there is to make this work and haven't slept all night trying to figure out

Honestly, any advice is greatly appreciated

 

[USAFRet]

Customizing proprietary workstations (Dell/HP) is always a losing proposition.

Standard stuff either does not fit, or has the wrong connections, or requires odd other components.

 

[js_maverick]

I do agree about customizing proprietary stuff as like a losing proposition. but if theres a will theres is always a way, be it it might be ugly.

I know I'm late to the party but I actually just had the same exact problem you did and I'm hoping you have not given up yet. I recently purchased a used sff z220 with a i7 4790 (non k) for a really good price that I could not pass up the chance. then I was face with similar problems that you have. I already knew what I was going to do with it which is transfer it to a spare pc case I had laying around I just took out the previous motherboard and kept the powersupply in it. doesn't look pretty and I had to dig into my spare parts and screws to secure the cooler into the motherboard unless you plan on changing the cpu cooler. now I had to deal with the power supply not being compatible with the proprietary intel c226 mothercoard that came with the system. so I did alittle research and bought a 24pin to 6pin for the sff z220 motherboard. now make sure that if is for your specific model since if you buy the wrong one you might have to rewire the adapter and that's not fun. and make sure you look up the motherboard layout for the other essentials like power pins and usb pins.

ps. I bought mine on amazon since I have prime and just searched "z220 24pin to 6pin" and you should get a few results for 24pin to 2x3/1x6 (if the last part confuses you it just means its for the 6pin power and the 6pin single row for the comm.

reply back if it solves your problem, happy modding!