New CPU cooler & re-seated smaller heatsink; now fans are LOUD and display is blank!!

[IrocD]

I have a HP Compaq Elite 8300 USDT/USFF pc- the reeeealy small one. I have it running 24/7 as a media server, and since heat kills, I wanted to upgrade the cooling a little bit. Since the form factor is so small, and a replacement/larger case is out of the question (as well as liquid cooling for now), I purchased the Noctua Low-Profile NH-L9I heatsink and fan.

While I was inside the PC, I thought it would be a good idea to remove the other smaller heatsink with the Z-clip and replace its thermal paste. I didn't realize this was not a regular paste setup, but it's actually glued on. I believe this heatsink is for the chipset/northbridge (correct me if I'm wrong?) but I did the best I could and applied paste and clipped it back on. It moved a little, but seemed like it would be okay.

Moving on to the cooler, the 8300 USDT has a passive cooler mounted to the processor and a small PWM fan in front and back of the case for cooling. I had to modify the case slightly to accomodate the new setup, which included hammering down the pieces of the back/bottom of the case that the OEM cooler mounted to, effectively removing my ability to go back to stock without figuring out how to re-mount the old cooler.

Anyway I get the cooler mounted, and use a PWM fan cable splitter to wire in the new fan with the front fan. I get everything all zip-tied up and perfect, and plug the beast back in. Immediately I notice that my monitor isn't doing anything (LCD tv connected by a DisplayPort-to-HDMI converter dongle) and then all three fans start spinning so loud it sounded like a jet engine taking off! This PC is quiet as heck, so this caught my attention real fast! I immediately shut it down. I remove the new fan and splitter, and just keep the two original fans connected to see what happens. Turn it back on, and the same sequence of events happens- nothing on the screen, and just eventually the fans go crazy.

I then wonder if maybe the CPU cooler is not making good contact with the processor? So I take it allll apart, remove the cooler and look at both sides- the TIM is perfectly spread, and I could tell it had made great contact. So it isn't that, and the PC barely had time to heat up! So then I wonder if I effed-up with putting the TIM under that small heatsink; so I take that off, clean the TIM off it and the exposed die underneath, and place it back on. I also pressed the BIOS reset button just in case, and tried it again. SAME THING!!

Tonite after work, I plan to hook up a monitor to the VGA port and see if anything can be seen on the monitor that way. But does anyone else have any suggestions? I really rely on this PC and don't have a lot of money to keep buying stuff to try and see if it fixes the problem. I've googled and I can't even be sure that the small heatsink is really on a chipset or northbridge; could it really be for the integrated graphics instead, and that's why I can't see anything on the monitor? HP's board layout pic identifies everything else BUT that. So any help is appreciated greatly! Thanks in advance!!!

[Anisio]

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