They are compatible but Socket 7 often has obstructions such as nearby capacitors that get in the way of larger Socket A heatsinks.

swaaye wrote on 2021-02-09, 18:25:

They are compatible but Socket 7 often has obstructions such as nearby capacitors that get in the way of larger Socket A heatsinks.

^This

Jackhead wrote on 2021-02-09, 18:06:

I compared the pictures of the two sockets. It looks like that is possible to fit a socket A cooler also on a socket 7 mainboard […]
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I compared the pictures of the two sockets. It looks like that is possible to fit a socket A cooler also on a socket 7 mainboard?
Anyone tryed that before?

https://de.wikipedia.org/wiki/Sockel_A
https://de.wikipedia.org/wiki/Sockel_7

And actually, in theory sockets 3, 5, 7, 370 and A are all the same size, but the older sockets may have increasing compatibility issues like the beforementioned caps and other motherboard components in the way and the Socket 3 socket often having missing tabs, limiting in practice what CPU HSFs can be installed without some creative modding.
Here's a bonus pic, the evolution of CPU HSF design of this fit is actually quite interesting.
download/file.php?id=37266&mode=view

I've used old Socket 370 coolers originally designed for Celerons on Socket 7 that fit well because they are usually smaller than contemporary PIII/Athlon heatsinks, but are still way overkill for most CPUs on S7, even the faster ones. I'm not as sure, but Duron coolers might work as well. Something like the CPU coolers from the third row down in the picture Tetrium posted.

athlon-power wrote on 2021-02-09, 22:38:

I've used old Socket 370 coolers originally designed for Celerons on Socket 7 that fit well because they are usually smaller than contemporary PIII/Athlon heatsinks, but are still way overkill for most CPUs on S7, even the faster ones. I'm not as sure, but Duron coolers might work as well. Something like the CPU coolers from the third row down in the picture Tetrium posted.

I presume you'r referring to these?
download/file.php?mode=view&id=102621
The 2 in red are stock Intel s370 CPU HSFs and are imo the best fit for s7 which has components blocking the vicinity of the CPU socket as these don't have any (or hardly any) overhang and are quite beefy (also the base is quite beefy).
I hate the stock clips though. Can't (easily) mount or demount them so I would swap out the retention clip with a different one. And the stock fans are often also quite noisy, so you might wanna replace those as well.

The CPU HSF to the direct right of the 2 marked ones is also a stock Intel CPU HSF, but it has more overhang and the CPU HSF directly below that one (the one with the holographic AMD logo on the fan) is a later stock AMD sA HSF, which works really great in Coppermine/Tualatin systems (IF you manage to actually mount it on a Tualatin CPU in a way that doesn't cause too much stress on the socket tabs that is, important to remember this).

In the row above the ones with the marked CPU HSFs, the most right one is a s7 CPU HSF which will fit anything s370 easily, but I wouldn't really recommend using such a CPU HSF on anything like a K6-III or a 800MHz or faster Coppermine (say, no more that 30W CPU power dissipation). It should work perfectly fine for something like a Pentium MMX though. Really quiet as well. Or use those fans (especially the quit ones which can also move decent amounts of air) as donor for the s370 stock Intel HSFs 😜

Yes i see also the caps near the socket as problem for the most cooler. I want to cool a K6 3+ with OC.
I also found this watercooler here:

What is really cool, i think was the first block from aquacomputer for socket A. Will try in the next day if this one fit on the Asus P5A.
Maybe than i build a SS7 watercooled system for fun 😀

In the past I had a Thermaltake Volcano 7 on a QDI socket 7 board.

But as pointed out in earlier posts it is very much dependant on the way how the socket is located in relation to capacitors etc.. You need sufficient free space around the socket for this type of heatsink which the QDI has because the socket is located at the side of the MB.
And there is, alas, not much free space around the socket on the ASUS P5A because it is surrounded by relatively high capacitors plus the socket for the psu cable.

Yes another idea was to use a copper plate between the heatsink and cpu to get out of the caps.
But i really hope the aquacomputer block will fit perfect. The side finish with the socket to get no trouble with the atx connector. I will see.

Seems to me like watercooling is overkill for a K6-III+. These don't get really hot anyway. These chips had TDPs of perhaps 20W at the very most. These chips are way cooler than the 2.4v K6-III and K6-2 parts for instance, which ran at perhaps max 30W or so.
With Athlon XP being able to move into the 70W range, even a stock AMD Athlon XP HSF is overkill for such a CPU.

There used to be a K6+ forum which contained a lot of valuable information about these chips (including overclocking and tweaking bits of info), but I'm unable to find it atm.

They are cross compatible but most Socket A coolers require clearance around the socket that Socket 7 motherboards do not have, so test fit in advance.

Well it might be overkill, but the water cooler itself is not up to date like the water blocks today.
Look at the waterflow .. It was the first cooler from aquacomputer "Cuplex" they made august 2001 so its not really something ordinary for the timeline.
Here a link from the company, sorry only german: https://www.aquacomputer.de/cuplex.html
Im lucky they still have some G1/8 connector for it because the rest is G 1/4 .
I dont expect to much from it. But when it cools down the K6 3+ something around OC 550-600MHz without problems im pretty happy with it.

Hope to get it end of the week i will give you some pictures than.

The cooler fits perfect, but i order to place it on the mount i have to desolder first the caps to not damage them. But ok.

installed, i had to leave the pwr_fan header removed:

Jackhead wrote on 2021-02-13, 09:47:

The cooler fits perfect, but i order to place it on the mount i have to desolder first the caps to not damage them. But ok. IMG_ […]
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The cooler fits perfect, but i order to place it on the mount i have to desolder first the caps to not damage them. But ok.
IMG_0785.JPG

installed, i had to leave the pwr_fan header removed:

IMG_0791[1].JPG
IMG_0793.JPG
IMG_0794.JPG

What were your results with this water cooled setup?

System runs fine on 550MHz, i dont have benchmarks any more because i skipped SS7 to a 586 S7.