Server Overload... what to check?

Hello everyone,

Our site went down yesterday, and the host had to reboot it.
They could ping the site, yet it wouldn't permit SSH access.

After they brought it back online, it crashed again.
I asked them for help again, and they had to reboot it once again.

Here is what the tech pasted in the ticket:::

Your server has been rebooted and its accessible. Following PHP scripts are overloading the server badly and load is increasing again:

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4490 account 36 18 22044 8552 6096 R 43.7 1.1 0:00.96 /usr/bin/php /home/account/public_html/forums/vbseo.php
4494 account 35 18 106m 28m 6652 R 30.8 3.7 0:00.37 /usr/bin/php /home/account/public_html/forums/vbseo.php
4501 account 34 18 102m 23m 6636 R 25.8 3.2 0:00.26 /usr/bin/php /home/account/public_html/forums/vbseo.php
4500 account 34 18 93440 54m 47m R 22.8 7.2 0:00.23 /usr/bin/php /home/account/public_html/forums/vbseo.php
4499 account 35 18 93436 34m 27m R 19.9 4.6 0:00.20 /usr/bin/php /home/account/public_html/forums/vbseo.php
4238 account 35 18 92772 28m 22m R 19.6 3.8 0:00.25 /usr/bin/php /home/account/public_html/forums/vbseo.php
4243 account 36 18 98196 17m 6464 R 12.5 2.3 0:00.14 /usr/bin/php /home/account/public_html/forums/vbseo.php
4245 account 38 18 98196 17m 6556 R 12.5 2.3 0:00.14 /usr/bin/php /home/account/public_html/forums/vbseo.php
4248 account 35 18 97172 15m 6268 R 11.6 2.1 0:00.13 /usr/bin/php /home/account/public_html/forums/vbseo.php
4247 account 39 18 97428 16m 6268 R 10.7 2.1 0:00.12 /usr/bin/php /home/account/public_html/forums/vbseo.php
4250 account 35 18 96148 15m 6392 R 10.7 2.0 0:00.12 /usr/bin/php /home/account/public_html/forums/vbseo.php
4249 account 35 18 95372 14m 6312 R 8.9 1.9 0:00.10 /usr/bin/php /home/account/public_html/forums/vbseo.php
4251 account 35 18 95372 13m 6180 R 8.9 1.8 0:00.10 /usr/bin/php /home/account/public_html/forums/vbseo.php
4252 account 35 18 95372 13m 6240 R 8.9 1.8 0:00.10 /usr/bin/php /home/account/public_html/forums/vbseo.php
4254 account 35 18 94080 13m 6140 R 7.1 1.7 0:00.08 /usr/bin/php /home/account/public_html/forums/vbseo.php
4255 account 36 18 92724 11m 5908 R 4.4 1.5 0:00.05 /usr/bin/php /home/account/public_html/forums/cron.php
4256 account 35 18 91696 10m 5628 R 3.6 1.4 0:00.04 /usr/bin/php /home/account/public_html/forums/vbseo.php

I just logged into vB cPanel, and disabled vBSEO.
The any idea what I can check?

Obviously, I messed up somewhere, as vBSEO has never caused problems.
The only other piece of information is that when these server crashed started (24 hours ago), we have had a really have increase in traffic to our site.
It is running on a dedicated server.

Any input as to what to check would be greatly appreciated.
Thank you!

UPDATE: Server loads are staying hovering in the 3.00-4.50
We usually see under 1.00 of load

One change that I did recently:
We have six CMS Article pages that get 90% of our website traffic.
Anticipating that traffic, and wanting to capitalize on it, I added Facebook Like buttons on the very top.
Maybe those are messing up something?

Facebook would run off facebook servers, not your own.

If you're getting more traffic and its shutting your site down, you need better hardware.

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