Asus H87I-Plus+i5-4590S=No POST, CPU is on supported list

[Bitter]

Ok, so I acquired an i5-4590S CPU, tested it in an OEM HP board and an Asus Z87I-Deluxe, CPU works correctly, both memory channels work, booted with both Windows and Linux, passed stress tests, the CPU works. I tried to install it in my HTPC, replacing my i3-4130 CPU, I made sure I had the correct BIOS revision and reset the BIOS to defaults prior to installing the i5-4590S CPU. Once installed the system will not POST. I swap the i3-4130 back into the system and it will POST and boots up fine into Windows 10.
Asus lists the CPU as supported since BIOS 1005, I have the latest BIOS, 2003 installed.
https://www.asus.com/us/Motherboards/H87...pDesk_CPU/
 
I've started a support ticket with Asus on this, but was wondering if anyone else here could shed some light on the issue or had first hand experience with the problem I'm up against. Swapping CPU's back and forth is a bit of a pain due to how the case is assembled and the small area to work. I have a free 4460S I might try later.  Asus tech support is less than stellar with their suggestion that my CPU must be faulty and then never replying when I told them that it's working fine in another Asus motherboard. Go figure. Oh but they bumped me up to priority level 2 now, ooooooo exciting!

I have a strong suspicion that this is a BIOS problem but I don't know how to check that, I have the BIOS .cap file and I wanted to try to open it and look around inside to see if maybe I can spot the problem but I'm lacking the skills to do that. If someone could just check the BIOS file and confirm or deny that as the issue with the CPU in question or guide me toward some step by step directions detailing how to do that myself I would greatly appreciate that. I would really like to learn how to check that myself as in the future I wish to edit the BIOS file of the Z87 board (and maybe the H87 board) to allow all cores max turbo as the S processors have ample thermal headroom.
https://dlcdnets.asus.com/pub/ASUS/mb/LG...I-2003.zip <-- current BIOS my H87I-Plus is using
The skinny:
Asus H87I-Plus No POST with 4590S, works fine with i3-4130. Suspect BIOS problem.

[DeathBringer]

Post a screenshot third (Mainboard) tab of CPU-Z with supported CPU.

Try this algorithm:
1) disconnect power cord
2) disconnect all HDDs and optical drives
3) remove all DIMMs and CMOS Battery
4) install new CPU
5) wait 10 mins
6) press and hold power button for 30 sec.
7) install CMOS Battery and one DIMM only in first slot.
8) connect power cord and try to power on.

[Bitter]

Post a screenshot third (Mainboard) tab of CPU-Z with supported CPU.

Try this algorithm:
1) disconnect power cord
2) disconnect all HDDs and optical drives
3) remove all DIMMs and CMOS Battery
4) install new CPU
5) wait 10 mins
6) press and hold power button for 30 sec.
7) install CMOS Battery and one DIMM only in first slot.
8) connect power cord and try to power on.

I can get the CPU-Z screenshot tonight, I'll give that process a go soon as it's the HTPC and we're watching things every night. I have tried it with a single DIMM in either A or B, but I haven't gone so far as to disconnect all the things. I'll post an update when I've completed that and let you know if it accomplished anything or not. I'll also try my 4460S as well if that doesn't get the 4590S working. Both require the same BIOS revision so if the 4460S also does not work then that would narrow it down closer to being a poorly made BIOS?

[Bitter]

Here's the CPU-Z mainboard screenshot. I'll be able to do the other things tomorrow evening and pending the expected outcome, the 4590S not POST'ing, I'll also try the same with the 4460S I have free.

[Bitter]

Ok, my 4590S is buried under a heatsink in another system at the moment so I'm using my free 4460S (also tested working in 2 other motherboards, the same ones that the 4590S works in as well). The i5-4460S results in an identical condition, no POST. I swap the i3-4130 in and the system will POST, I swap the 4460S back in and it will not POST. When I say no POST maybe I should be more clear. I get fans on for the chassis and CPU cooler as well as the video card but there is no video output, I've tried with HDMI and DVI on two different displays, I've tried the onboard video as well.

How would I open that BIOS file to look at the contents and what would I be looking for? Since the no POST happens with both low power i5 CPU's both of which required the same BIOS version update (which I am updated past) I strongly suspect a problem within the BIOS programming. Asus tech support is pretty much ghosting me with no reply until I ask them for an update and then the same 'we're working really hard' line. I highly doubt I'll get any help from them but if I do I'll add it to the thread. Also thank you for moving this, I didn't think this was the correct section since I'm not trying to upgrade to an unsupported CPU, just trying to get supported ones working like they're supposed to.

Next steps you would suggest?

[DeathBringer]

Did you tried to use my algorithm? Try to downgrade version of BIOS.

[Bitter]

Yes, I followed your directions precisely.
I'll try to downgrade to the version that first supported the S series i5 CPU's tomorrow, I'm not sure the Asus BIOS flash utility will allow downgrade, I'll find out and report back.

[Bitter]

I figured out how to turn the .cap into a .rom and open it with AMIBCP4.55.0070 but beyond that I haven't figured out what to do with the tool or where to look to try to figure out what's wrong with the BIOS, if anything is. I did find the CPU ID of the 4590S is 306C3 so I assume that has to be listed somewhere in the BIOS for it to recognize the processor and start the process to POST and then boot.

I'm trying to push forward and learn some of this on my own, I appreciate your help so far though.

[Bitter]

So I figured I'd update my resolution for this issue in the hopes that someone searching here or on google can fix this for themselves as well. The BIOS updater you can access from BIOS is broken, it applies the new BIOS number but makes no actual changes to the BIOS to update it. You MUST use the Windows based tool to update the BIOS, that works correctly. I'm now running the current BIOS on the board and another board I bought for something else and all the correct CPU's are working where they should be. This was a supremely frustrating issue and Asus support is unaware of this, I was lucky and hit the google search term jackpot finally and hit a Reddit post linking to somewhere else about the issue and how to fix it.

[qwerty1]

So I figured I'd update my resolution for this issue in the hopes that someone searching here or on google can fix this for themselves as well. The BIOS updater you can access from BIOS is broken, it applies the new BIOS number but makes no actual changes to the BIOS to update it. You MUST use the Windows based tool to update the BIOS, that works correctly. I'm now running the current BIOS on the board and another board I bought for something else and all the correct CPU's are working where they should be. This was a supremely frustrating issue and Asus support is unaware of this, I was lucky and hit the google search term jackpot finally and hit a Reddit post linking to somewhere else about the issue and how to fix it.

Absolutely thanks! I didn't know what to do with my ASUS H87-plus not reading my i5 4460s (no screen signal when turning on PC). I updated the BIOS using EZ flash from BIOS but didn't work. Then updating from Windows worked!

In Windows 7 I previously installed Management Engine Interface V9.5.15.1730 and then BIOS updater for New 4th Gen Intel Core Processors v2.00.02 with BIOS v2003, all from official ASUS H87-plus website. 
Only this two steps and my i5-4460s is perfectly working now!