What's the make and Model number of your PSU ? You do you have latest BIOS installed on your system ? Did you connect the 6-pin power connector/cable to the GPU ? Are you booting in Legacy or UEFI mode ?
IMO, that's not a very good/reliable PSU brand, if I'm not mistaken.
I wouldn't use this to power up any gaming PC though. Also depends on the model and who built it (OEM).. If it's Delta or CWT, you're okay-ish, they should be good/average. If it's Sirtec stay away. Chieftec have had horrible reviews/PR in late 2000s/early 2010s, though I haven't heard much about them recently.
The bottom line here is that Cheiftec isn't a known brand at least in the US, so most people just assume that they aren't very good since they haven't heard of them.. They use a variety of OEMs from Delta for some cheap and unimpressive models, to Sirfa/High Power and CWT for most of the remaining lineup. Not sure about your particular OEM.
Replace the PSU. Cheiftec makes nothing but garbage. They are extremely low quality.
Let's start with the biggest misconception out there, which is that if a unit has high watts it will be ok or is good. Well, that couldn't be further from the truth.
There are plenty of 750-1000w units out there that I wouldn't trust to power a light bulb and might in fact be more dangerous due to their supposedly high capacity due to poor or non-existent protections inside the unit.
If the platform isn't good to begin with, how many watts or amps it says it can support is irrelevant.
Higher 80plus certification doesn't mean anything, UNLESS it is a PSU platform that we already know is good anyhow. For example, a Seasonic Prime platinum unit is going to be a better product than a Seasonic Prime Gold unit, because we already know the Prime platform is very good, and platinum efficiency along with it shows there are some improvements internally to account for the higher efficiency.
In a case like that, it might be worth it. It's likely the unit will create less heat, it will probably have better performance in regard to ripple, noise and voltage regulation. It might shave a few pennies, or dollars, off the electric bill over the course of a year.
Other than that, it is not going to perform any better than the same platform with Gold efficiency. On the other hand, just because a unit has Titanium 80plus ratings doesn't mean the unit is any good at all. For example, there are Raidmax units with Titanium efficiency and I wouldn't trust one of those to power a light bulb. There are a lot of units like this out there.
If the platform isn't good to begin with, whether or not it has an 80plus certification or not is irrelevant.
Whatever you do, don't EVER buy a power supply based on whether it has RGB or lighting, or looks like it might be a quality unit. Some of the biggest hunks of junk out there look just as good as a Seasonic Prime Ultra Titanium, but I assure you, they are not. So far there are very few very good units out there that have RGB built in. Maybe one or two models, but rest assured you'll be be paying for the lighting, not for the quality of the power supply.
I don't know what country you reside in, and I know that sometimes it's hard to come by good units in some regions, but when possible, when it comes time to get that PSU, I'd stick to the following if you can.
Seasonic. Seasonic isn't just a brand, they are a PSU manufacturer, unlike many of the PSU brands you see they make their own power supply platforms AND a great many of the very good PSU models out there from other brands like Antec, Corsair and older XFX are made by Seasonic.
Just about anything made by Seasonic is good quality for the most part. There are really no bad Seasonic units and only a very few that are even somewhat mediocre. They do make a few less-good quality OEM style units, but mostly those are not going to be units you come across at most vendors, and they are still not bad. Also, the S12II and M12II 520 and 620w units are older, group regulated models. At one time they were among the best units you could buy. Now, they are outdated and not as good as almost any other Seasonic models. They are however still better than a LOT of newer designs by other manufacturers.
The Seasonic 520w and 620w S12II/M12II units CAN be used on newer Intel platforms, if you turn off C6/C7 in the bios, but I'd really recommend a newer platform whenever possible. Prices are usually pretty good on those though, so sometimes it's worth accepting the lack of DC-DC on the internal platform. Higher capacity versions of the High current gamer are not based on that platform, so they are fine. Those being the 750w and higher versions.
Most common currently, in order of preference, would be the Seasonic Focus series, then Focus plus, then Prime, then Prime ultra. It's worth mentioning that there are generally Gold, Platinum and Titanium versions within each, or most, of those series, but that does not necessarily mean that a Focus plus Platinum is necessarily better than a Prime Gold. It only means that it scored better in the 80plus efficiency testing, not that the platform is better.
Again, don't let yourself get tangled up in the idea that a higher 80plus rating specifically means that it is a better unit than another one with a lower rating, unless you know that it is a good platform from the start. All these Focus and Prime units are pretty good so you can somewhat focus on the 80plus rating when deciding which of them to choose.
Super Flower. Super Flower is another PSU manufacturer. They are like Seasonic and they make power supplies for a variety of other companies, like EVGA. Super Flower units are usually pretty good. I'd stick to the Leadex, Leadex II and Golden Green models.They also make most of the good units sold by EVGA like the G2, G3, P2 and T2 models.
Super Flower doesn't have a very broad availability for the units with their own brand name on them, and are not available in a lot of countries but for those where there is availability you want to look at the Leadex and Leadex II models. The Golden green platform is fairly decent too but is getting rather long in the tooth as a platform AND I've seen some reviews indicating a few shortcomings on units based on this platform.
Even so, it's a great deal better than a lot of other platforms out there so you could certainly do worse than a Golden green model. Units based on the Leadex and Leadex II platforms are much better though.
Corsair. The CX and CXm units are ok as a budget option, but I do not recommend pairing them with gaming cards. The newer 2017 models of CX and CXm are better than the older ones, but still not what we'd call terrific, so if it specifically says 2017 model, or it has a capacity other than an even 100, like 550w, 650w, 750w, etc., then it's likely at least better than those older ones. Aside from that, any of the TX, RMx, RMi, HX, HXi, AX or AXi units are good. Those are listed from best to worst, with the best being the AX and AXi units.
Antec. The True power classic units are made by Seasonic, and are very good, but are not modular. The High current gamer 520w and 620w, or any other PSU you see on the market that is 520w or 620w, are also made by Seasonic, based on the S12II and M12II platform for modern versions, and are pretty good units but again they are an older platform that is group regulated so if you go with a Haswell or newer Intel configuration you will want to avoid those because they do not support the C6/C7 Intel low power states.
The Antec High current gamer 750w and 850w units are very good and are not the older design, which came in 520w and 620w capacities and were good for back then but again, are an aging Seasonic platform that is not the best choice most of the time these days. Occasionally, these older units MIGHT be the best unit available and you could do worse than one of them, but a newer DC-DC platform is desirable when possible if it doesn't mean sacrificing quality elsewhere in the platform. There are however older and newer HCG models, so exact model number will likely be a factor if choosing one of these however both the older models and the newer models are good.
Antec Edge units are ok too, but reviews indicate that they have noisy fan profiles. I'd only choose this model if it is on sale or the aesthetics match up with your color scheme or design. Still a good power supply but maybe a little aggressive on the fan profile. This may have been cured on newer Edge models so reading professional tear down reviews is still the best idea.
Antec Earthwatts Gold units are very good also.
BeQuiet. BeQuiet does have a few decent models, BUT, you must be VERY selective about which of their models you put your trust in. From model to model their are huge differences in both quality and performance, even with the same series. If you cannot find a review for a BeQuiet unit on HardOCP, JonnyGuru or Tom's hardware that SPECIFICALLY says it is a very good unit, and does not have any significant issues in the "cons" category, I would avoid it. In fact, I'd probably avoid it anyhow unless there is a very great sale on one that has good reviews, because their units are generally more expensive than MUCH better units from Antec, Seasonic, EVGA and Corsair.
EVGA. They have BOTH good and not very good models.
Not very good are the W1, N1, B1, B3 (Most models failed testing), BQ, BR, BT and G1 NEX models.
Good models are the B2, G2, G2L, G3, GQ, P2 and T2 models.
FSP. They used to be very mediocre, and are a PSU manufacturer like Seasonic and Super Flower, although not as well trusted based on historical performance. Currently the FSP Hydro G and Hydro X units are pretty good.
I would avoid Thermaltake and Cooler Master.
They do have a few good units, but most of the models they sell are either poor or mediocre, and the ones they have that ARE good are usually way overpriced.
This is just ONE example of why I say that. Very new and modern CM unit. One of the worst scores ever seen on JonnyGuru for a well known brand name product. Doesn't look to be much better than a Raidmax unit. Sad.
The Powerspec units sold my Microcenter are a mixed bag. Some of them are fairly decent using the same platform as the Sirfa High power astro lite platform, so not total dumpster fire type units, but not particularly good either, and some of their units are simply garbage and should be listed below in the DO NOT USE category, but I'm leaving them out because there are really no reviews of them and since there are a few units from them that are ok-ish, I'm giving them a "use at your own discretion but buy a better model if you can" grade.
A gray label CX or CXm unit would probably be an upgrade from one of those Powerspec models, without any doubt.
Certainly there ARE some good units out there that you won't see above among those I've listed, but they are few and far between, much as a hidden nugget of gold you find in a crevice among otherwise ordinary rocks and don't EVER assume a unit is good just because of the brand.
If you cannot find an IN DEPTH, REPUTABLE review on Tom's hardware, JonnyGuru, HardOCP, Hardware secrets (Old reviews by Gabe Torres), Kitguru (Only Aris reviews), TechPowerUP, SilentPC crew or a similar site that does much more than simply a review of the unboxing and basic tests that don't include reliable results for ripple, noise, voltage regulation and a complete teardown of the unit including identification of the internal platform, then the unit is a big fat question mark.
I recommend not trusting such units as companies generally always send out review samples of any unit they feel is going to get a good review, and don't send them out if they know they are going to get hammered by the reviewer. No review usually equals poor quality. Usually.
Other models that should never be trusted OR USED AT ALL, under any circumstances, include
A-Top, AK Power, Alpine, Apevia, Apex (Supercase/Allied), Artic, Ace, Aerocool (There might be one model worth using, but I'd still avoid them.), Aspire (Turbocase), Atadc, Atrix, Broadway com corp, Chieftech, Circle, CIT, Coolmax, Deer, Diablotek, Dynapower, Dynex, Eagletech, Enlight, Eurotech, Evo labs, EZ cool, Feedtek, Foxconn, G7, HEC/Compucase Orion, HEDY, High power, iBall, iStar computer co., Jeantec, JPac, Just PC, Kolink, LC Power, Linkworld electronics, Logisys, Macron, MSI, NmediaPC, Norwood Micro (CompUSA), Okia, Powercool, Powmax, Pulsepower, Q-tec, Raidmax, Rave, Rocketfish, Segotep, SFC, Sharkoon, Shuttle, Skyhawk, Spire, Startech, Storm, Sumvision, Tesla, Trust, Ultra, Wintech, Winpower, Xilence (Until I see a reputable review of a model showing different), xTreme (Cyberpower), Youngbear and Zebronics.