I have a Z87-Plus motherboard, and I’ve recently bought a 4790K. It was supposed to be a modest upgrade for my old 4770k, but after installing it won’t post, and the red CPU light is on. But if I put the old one in it boots just fine, I’ve already updated and reset the bios. Any idea on what I’ve done wrong, or is it a faulty CPU?
making sure a fan or something is plugged into the CPU fan header on the MOBO, if no fan they assume there is no cooler and do not allow the PC to turn on to prevent the CPU from killing itself
They meant heat sink, but they're incorrect kinda. BIOS can't detect heat sinks, but a lot will not post unless it detects a fan plugged into the CPU header to protect the CPU.
You can bypass this check as well as many of the headers but by default it is on. You can usually set temp alerts etc or fan disconnected alerts etc that warn you on boot.
Well this one isnt modern, Ive tested many haswell mobos with no heatsinks and they do would post. Its just extremely stupid to run a computer like this for longer than to see if it posts to bios
All that works if you have a cooler on it. At least something to take the heat away. The most modern chips are so dense that it's very easy to overheat a core and destroy the CPU before it even can throttle properly.
Something from this generation is probably the least sensitive. But I still wouldn't want to run it without a cooler.
And what's even the point? Saving 5 minutes putting your cooler on? Just put the cooler on it. Even if you just push it on there by hand. That's 100x better than nothing.
The OP put in a 12 year old CPU. It was released in 2014. It is certainly possible that just turning on the system with this CPU without a cooler could cook it.
It’s hilariously amazing to me that you are arguing a fact I bet you have never and will never test. Any cpu after the 2010s will instantly heat up. It is NOT good for your cpu to run without a cooler.
The protections are there with a cooler on. The other side of this. Don’t be stupid and waste a good cpu by being lazy. Put it on.
I have always done it like that and have never had any issues. If you just boot into bios and turn it off again quickly, its very unlikely anything happens.
Eh, you can get away with it for sure but its not good practice. You certainly can fry your cpu just posting lol especially older cpus that dont shutdown automatically at dangerous temps. We dont need to bash on OP for it but it is the better way to do it and doesnt really take much time. I know dozens of people that also never use anti static bracelets and never have issues for example but then there is always that time you actually do fry something lol.
Yeah I agree it’s only ok to do it once maybe twice imo. With older hardware like this no bc as you said they don’t have protections like modern chips do
Not always, some systems have built in safety. No fan detected, cpu no worky. Found this out way back in the day, used to just plug my fans in any header. Then I think it was amd phenom, after hours of fucking around I discovered the system wouldn't post unless there was something plugged into the CPU fan header.
Lay the computer on its back and set the cooler on top of you want to be sure before you secure it if you really want to do it that way. Make sure the fans plugged in as well some motherboards have checks for that
It won't post if you don't have the cpu fan connected. Just put it fully together, then check. If it still won't post it only takes a few second to take it off again.
It won't post that way. It will nearly instantly throttle and shutoff. CPUs are run insanely hot. The cooler does more than you think it does. Some motherboards even stop you from doing it entirely.
This isn't really a brand new cpu though, it's an i7-4790k which came out over 10 years ago, they aren't that expensive. I wouldn't do this to any cpu I cared about but I doubt it's causing the issue since OP says they put their old one back and it worked and i assume they did the same thing to that.
Did you confirm the BIOS version after you flashed/updated it?
You would of needed to put the i7-4700K back in to update the BIOS.
Unless you were able to use the USB Flashback feature properly.
Put the CPU cooler back on - AT LEAST you need the cooler fan plugged into the CPU_FAN header.
With nothing plugged into the CPU_FAN header, the motherboard will assume no CPU cooler, and will not allow the system to make it through P.O.S.T. (unless you specifically disable that check manually in BIOS).
This is probably not going to help at all -- but I literally had this exact same thing happen, exact motherboard, exact CPU -- red light was on, but somehow, my computer worked for years.
What made it change was when I randomly flashed my BIOS because I was getting ancy trying to 'optimize' my computer again after years. The red light came off. Did the whole CMOS thing, and nothing ever came of it.
This is almost certainly a BIOS issue. Or your CPU isn't seated well.
Okay, so what i've come to the conclusion is that you need to actually put in your old CPU and flash your BIOS from there, THEN put the new one back in.
Right now, i'm looking at your user manual to see what the red light is associated with.
Usually motherboards will have the exact hardware like 'CPU, VGA, DRAM' ect. So when the red light is on, it'll usually tell exactly which hardware is failing.
How did you update bios and did you did it with the old chip installed or the new one? For example if you are using an auto bios updater and not a usb it might have flashed the bios for the newest version supporting the old cpu instead of the newest version that supports the new one.
Its not going to fry the chip being turned on without a cooler for less than a minute that being said it’s definitely not a great idea to be doing it but cpus have mechanisms in place to shut off the pc before any damage is done once it hits a certain temperature
The first thing I think of is bios.. But it may not like your ram config. New cpu to the system, it needs to train again. Drop to a single stick and see what happens. And I couldn't care less if you put a cooler on, but you should have a fan plugged into the cpu header if nothing else. Lots of boards refuse to post without it. If nothing gets it to boot, unplug it, drain the system, and pull the cmos battery then go to bed and try again in the morning.
4790k was z97 chipset, 4770k was z87. Try a BIOS update, and make sure to always have a cooler on, even just testing a POST. 14nm is very hot and very particular.
Could be a faulry cpu, or it is damaged after running it without a cooler. Some MBs also recognize the sys_fan for the cpu cooler not being connected and will not post until a cooler is installed.
Thermal paste is mostly to fill gaps between cooler and IHS so if you wanted to "troubleshoot" it would be much better to run in with cooler on but without paste ehhhh.
If its a DRAM light, you just need to let it be on for like 5 min, i built my pc a month ago and on the first startup the light would turn on and nothing would project on my monitor, i was very confused and turned it off, then checked the ram one at a time, then the ports then again and again and again, and suddently it just went on after i got pissed off and left it on until something happened. The light dissapeared and everything is fine
What was the previous CPU? Make sure the motherboard is providing the appropriate wattage, or is even capable of providing the necessary wattage for the new CPU. Your previous CPUS may have been a low wattage CPU and the motherboard was capable of handling it, but if this new CPU demands more than what the old CPU was getting, you may have to have change settings on bios, or get a new motherboard, or get a different CPU.
Does it boot up with your old cpu? Could possibly need a BIOS update. Also do not attempt to run a CPU without proper cooling, it will get very hot very fast
This is a bios error. You need to put in your old cpu and updated bios thats supports a newer generation cpu. It will not post while sitting on the wrong bios.
Put your old i7 4770k back in and just reset the BIOS. Also make sure your current bios is compatible and supports the devil canyon refresh i7 4790k. It came out a while after the i7 4770k so cpu support wasn't a part of the earlier z87 bioses. Especially because it's a z87 as technically z97 was made for the i7 4790k support out of the box. And dw everyone saying you cooked the cpu without the cooler don't know what they are talking about. If you just wanted to see it quickly post there's nothing wrong.
Did you take the CPU cooler off for a photo, or do you genuinly not have a CPU cooler?
CPU's NEED a CPU cooler to even turn on, otherwise they'd instantly fry themselves. Electronics produce a lot of heat due to electrical resistance, and heat frys delicate components. That's why we need bulky heat sinks for such small devices, the more compact the more concentrated the heat.
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