Should I get a new PSU after my recent upgrade?

I think you've said this before, but there is NOT a problem with running adapters provided the power supply has sufficient power.

I don't recognize his power supply, but it certainly has sufficient power for his needs and getting a new one will change nothing.

His system only needs roughly 325 Watts max, or about 50% load.

*If he's being "held back" it's likely something else. (I'd probably still get a different power supply for the sake of knowing I have a quality unit but it's about reliability not power).

His PSU seems to be this:

http://www.ebay.com/itm/IBM-LENOVO-THINKSTATION-S20-625W-POWER-SUPPLY-FS8003-41A9759-41A9758-/232150905656

It looks like a pretty standard crappy PSU that companies shove into prebuilt PCs but I am pretty sure that it has enough power to not hold back the system.

You have around 200W on the 12V rail and your 1070 needs around 160W total.

The Seasonic is easily the better quality unit and please don't create another thread for an issue keep it to one.

1) I personally like one of the ECO models from EVGA such as the G2 because it can turn off the fan, and is also modular which avoids cable clutter.

You can lookup reviews as well. The differences between many of them are minor but some are louder than they need to be. I bought my dad a Be Quiet! model which is dead silent and has good reviews.

2) Just FYI, but the adapter is using the SAME EXACT POWER from the power supply whether it's through the PCIe cable or through the MOLEX adapter cable.

The purpose of different cables in part is to prevent people drawing too much power but the mains power is still delivered by the 12Volt rails (about 80W of the GPU power goes through the main 24-pin cable to the board then to the card, and the remaining 100W or whatever comes through the adapter cable or true 6-pin if you had a normal PSU).

(We could dissect the PSU further as to how separate the rails truly are but it's not necessary based on the power draw)

So if you're concerned about power supply failure or it's a noise issue by all means buy another one but if your performance is lacking again it's probably a DIFFERENT ISSUE. You should be running BENCHMARKS and comparing to similar builds or looking at the GPU load in specific situations.

*If the GPU frequency is high, AND the GPU load is also high (such as 1900MHz, 95% load) then you obviously aren't power starved and the GPU is running flat out.

(Just FYI the Unigine Valley and probably Heaven benchmarks don't show GPU frequency correctly. Don't use the program. Use the tool from your GPU company like EVGA Precision X for EVGA cards)

*And keep that power supply just in case you need to troubleshoot. Even brand new, high quality PSU's can still fail.

3) PCPARTPICKER. http://pcpartpicker.com/products/power-supply/
You can FILTER by "modular", price, wattage etc. (note that 80-plus ratings of GOLD etc are an efficiency rating and do not necessarily denote quality. A BRONZE can be better quality than GOLD. Probably not but it can be.

a) $90 - THIS one can disable the fan (ECO MODE) at 50% load which is why 650W makes sense for you if interested in that

there are cheaper PSU's that will work fine. depends what you want. A good PSU is an investment and can last 10 years.

Why EXACTLY do you not think your GTX1070 isn't performing properly or is bottlenecked somehow?

*And after rereading your post, that PSU sounds like it's reasonably new. Shouldn't be any problems. Lenovo would be rebadging one of the other units likely and it's probably fine but suit yourself.

Not your CPU.
Probably not your GPU (at least likely not a power issue).

Have you tried forcing FAST SYNC for CSGO?

NCP-> manage 3D settings-> add game-> FAST SYNC-> save

(Your output must be at least 2x the refresh. For example, if 144Hz you need over 288FPS... basically the GPU draws frames as quickly as possible and the LAST complete frames before the new refresh is the one used. So all other frames are dropped but it reduces LATENCY but at the same time eliminates screen tear.

Sometimes high refresh rates don't produce much obvious screen tear. Sometimes however it can cause tear and even cause STUTTER issues though there are several things that can produce stuttering. Usually it's a software issue.)