Help identify CPU

[cb2000]

Hi all, I've been checking out this forum for a while now, but, this is my first post and will probably post more since I am starting my first vintage PC build. Anyway, somewhere along the way I have got a CPU that I forgot about and can't identify. I was hoping that someone here may know what it is. Pictures below.

 

[GiGaBiTe]

It's a 200 MHz Pentium MMX Overdrive.

The problem is that it's unusable in that state. Not only is the integrated heatsink/fan assembly missing, so is the voltage regulation board. These parts are not supposed to ever be removed, it looks like someone forcibly pried them off. Even if you could get some sort of heatsink to mount to the chip without crushing the delicate surface mount components, the CPU probably won't work at all.

Here's what the chip is supposed to look like:

 

[cb2000]

ignore post

 

[deathshadow]

I've seen a LOT of those screwed over that way. It's like people keep seeing that glued-on sink and go "oh this HAS to come off" -- and in the process turn a fairly rare chip into useless broken junk.

 

[cb2000]

Thanks for the help gigabite. Fit for the bin then.

It's a shame alright, and I imagine it would of been hard to remove, but there you go.

 

[GiGaBiTe]

The heatsink is epoxied to the CPU, so yes it's extremely difficult to remove. But it's worse than that, the heat from the CPU tends to bake the epoxy and make it even harder. I've had to remove a fair few epoxied CPU/GPU heatsinks over the years, it's a PITA.

I wouldn't toss it though because the 200 MHz overdrive is one of the rarer and more expensive overdrive parts. You might be able to get a slower overdrive and cannibalize the VRM and heatsink off of it to make that one work. And if you wanted to go the extra mile, you could reverse engineer the VRM board and make a replica so both could work. The heatsink would be a bit of a challenge though. I think a chipset heatsink might work with it, since they sometimes come with round bases.

 

[cb2000]

I'll hold onto it then. Being that these thing were glued on though what kind of glue do you think I could use to glue another one back on?

Reverse engineering is a bit out of my league, so, I'll stick to cannibalizing.

 

[GiGaBiTe]

Any non-acid curing thermal epoxy should work, or if you don't want to get that, normal non-acid curing epoxy on the edges of the heatsink and a decent amount of normal thermal compound in the middle. Just stick it on after that and wait for it to set.

An alternative would be sticky thermal pads:

https://www.ebay.com/itm/151681154470

Thermal pads were common back in the late 486-Pentium era and worked fine most of the time.

 

[cb2000]

I've never seen those thermal pads before, but they seem like the best choice, especially since I could (if need be) use them in my upcoming 486 build. I had no idea they used that for the 486s, my ones back in the day had no heatsink, but I never had anything faster than a 33mhz.
Thanks for the help

 

[GiGaBiTe]

486s didn't need heatsinks until 40-50 MHz.

 

[Naguissa]

486s didn't need heatsinks until 40-50 MHz.

I had an Intel 486 DX-50MHz (not a DX2!) and it hadn't heatsink....

 

[GiGaBiTe]

I had an Intel 486 DX-50MHz (not a DX2!) and it hadn't heatsink....

It was running smokin' hot then.

 

[Naguissa]

It was running smokin' hot then.

I remember burning my fingertip when I touched it while working....

But still it was reliable. Even 4+ years after buying it, when Pentium 200MHz+, PCI (this machine was Vesa Local Bus) and Windows 95 were the norm, and I was using Windows 3.11, Win32S and WinG to try running modern applications on its scarce resources...

 

[deathshadow]

I'll hold onto it then. Being that these thing were glued on though what kind of glue do you think I could use to glue another one back on?

Safest bet -- and it would do double duty for you -- would be Arctic Silver's thermal adhesive.

http://www.arcticsilver.com/arctic_silver_thermal_adhesive.htm

I've used it on aftermarket video RAMsinks on Radeon 9xxx series boards a lot, since if you bother putting sinks on them you can usually get another 15% memory clock off them. It's how my old Radeon 9500 Pro in the Athlon era ran circles around the 9800's.

Would probably be far more efficient than whatever Intel used.

But then, more efficient than what Intel used is still going on. See the whole "de-lidding" thing. I cracked the lid off my i7 4770k and replaced the thermal paste with Thermal Grizzly Hydronaut (after conformal coating) and now set to 4.4ghz overclock my idle temps are 5C over ambient (in a 19C temperature controlled room) and peaks after running prime95 for an hour are at 55C... and those temps are on a air cooler -- admittedly a big bad Phantek TC-14PE. That's a full 10C drop at idle and 30C drop under load over the stock TIM between the die and spreader and TX-4 between the spreader and sink.

Fun times.